Moparts
vibration update on the cuda #2
Posted By: cudadan
vibration update on the cuda #2 - 09/27/08 06:33 PM
well if some of you remember i had a vibration in 3rd gear and 2nd it would go away, well i just had the trans redone with ALL new inside, just the housing was the only thing i reused, then i had the converter sent out and had it all redone. well i get out on the highway today get up to about 80 mph and the vibes are still there. the only thing that wasn't changed was the rear housing and leaf springs. Is there anything else i could look for? its only in 3rd gear. i went over every nut and bolt in the drive tran and all was good as were the motor mounts and tranny mount. all the bushiing in the leaf springs are in great shape too. I am at a total loss here.
Posted By: Cab_Burge
Re: vibration update on the cuda - 09/27/08 06:45 PM
Put the car up on jack stands so the weight is on the suspenion and have some one run the car up to the speeds that it vibrates at and see if you can find out what is causing it by looking at the car from underneath. If it doesn't vibrate on the jack stands maybe the vibrations is coming from the front of he car
Posted By: smokinwoody
Re: vibration update on the cuda - 09/27/08 06:47 PM
didnt you have the drive shaft rebalanced and NEW U joints added?
Posted By: Defbob
Re: vibration update on the cuda - 09/27/08 06:51 PM
tire balance or pinion angle
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 06:52 PM
i've tried all of the above.3 new drive shafts, changed pinion angle and ran it on the stands, it has the vibes on the stands but just cant find from where, i've changed tires and wheels, brake drums, center section, yokes,axles. tranny and torque converter. still something is causing the rear u joint to go bad
Posted By: Anonymous
Post deleted by Defbob - 09/27/08 06:58 PM
Posted By: smokinwoody
Re: vibration update on the cuda - 09/27/08 06:58 PM
this may sound dumb..
is there enough play in the slip yoke to the tranny where the suspension going up or down that would cause bind in the U joint..
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 07:10 PM
Quote:
junk the car 
LOL i have been known to do that LOl
yeah woody there is enough end play i made sure of that,
Posted By: smokinwoody
Re: vibration update on the cuda - 09/27/08 07:16 PM
my Camaro has a vibration now after I bottomed out on a bump in the road...after that it now has a vibration at certain rpm's..I must have hit the driveshaft ...problem is its one of those MATRIX shafts ...
have you checked the harmonic balancer...or had anything looked at in the engine...
Im thinking you already did all that..
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 07:19 PM
Quote:
my Camaro has a vibration now after I bottomed out on a bump in the road...after that it now has a vibration at certain rpm's..I must have hit the driveshaft ...problem is its one of those MATRIX shafts ...
have you checked the harmonic balancer...or had anything looked at in the engine...
Im thinking you already did all that..
i ahd the stock balancer on it then went to an SFI one and still there, i would think if it was the motor that it would do it all the time, and if it was the motor also i'd think the front u joint would go before the rear.
Posted By: smokinwoody
Re: vibration update on the cuda - 09/27/08 07:26 PM
not only do I ask dumb questions but I dont read..
rear U joint...pinion yoke?
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 07:32 PM
Quote:
not only do I ask dumb questions but I dont read..
rear U joint...pinion yoke?
LMAO, i tried 2 different yoke, a small one and now i run a 7290 series on it. still the same, this all started when i had the trans redone last winter.thats why i thought it was the trans. but i changed everything in the trans but the housing, i looked over it and no cracks andywhere either
Posted By: Anonymous
Re: vibration update on the cuda - 09/27/08 07:45 PM
Guess you do have the correct converter and balancer for a 360 being externally balanced?
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 07:48 PM
Quote:
Guess you do have the correct converter and balancer for a 360 being externally balanced?
yeah the car has been together for awhile , then this started,
Posted By: bobby66
Re: vibration update on the cuda - 09/27/08 07:59 PM
Wheel and axle bearings good?
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 08:03 PM
Quote:
Wheel and axle bearings good?
changed them all
Posted By: Al_Alguire
Re: vibration update on the cuda - 09/27/08 08:12 PM
Driveshaft....
Posted By: KatFysh
Re: vibration update on the cuda - 09/27/08 08:20 PM
I cracked a second tailshaft housing 3 weeks ago. I'm finally ready to go tear it apart tomorrow. What I'm gonna do is drop 3 lines. One from the balancer, 1 from the trans tailshaft and one from the rear pinion yoke. Then gonna check it with a laser level to see where the line runs from front to back. I'm thinking on mine that I may be off side to side with my trans crossmember. Also, did you use a new crush sleeve when you swapped yokes? I didn't on mine and that is another thought I had. Maybe the pinion isn't set correctly creating the vibrations.
But I'm not getting any groaning noises.
What I guess I'm asking here is, do you think that with all the times that you've had yours apart, that maybe the tailshaft isn't located exactly where it was before all this started, up/down & side to side
? When was the very time you took it apart for this problem? What was wrong then?
Posted By: hot67cuda
Re: vibration update on the cuda - 09/27/08 08:30 PM
run it on the stands with the tires off. put all the lug nuts on it .have someone turn one of the axles with a dail indicator on the flange watch the run out do the same for the driveshaft u find it.If they check out good it could br a ring gear out of balence.
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 08:34 PM
Quote:
run it on the stands with the tires off. put all the lug nuts on it .have someone turn one of the axles with a dail indicator on the flange watch the run out do the same for the driveshaft u find it.If they check out good it could br a ring gear out of balence.
did that too and all was good. this is the worst problem i ever had
Posted By: smokinwoody
Re: vibration update on the cuda - 09/27/08 08:36 PM
and this is an 8 3/4 rear?
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 08:37 PM
Quote:
I cracked a second tailshaft housing 3 weeks ago. I'm finally ready to go tear it apart tomorrow. What I'm gonna do is drop 3 lines. One from the balancer, 1 from the trans tailshaft and one from the rear pinion yoke. Then gonna check it with a laser level to see where the line runs from front to back. I'm thinking on mine that I may be off side to side with my trans crossmember. Also, did you use a new crush sleeve when you swapped yokes? I didn't on mine and that is another thought I had. Maybe the pinion isn't set correctly creating the vibrations. But I'm not getting any groaning noises.
What I guess I'm asking here is, do you think that with all the times that you've had yours apart, that maybe the tailshaft isn't located exactly where it was before all this started, up/down & side to side ? When was the very time you took it apart for this problem? What was wrong then?
i did put a new tail shaft on too. and when i changes yokes i did not put a new crush sleeve in, it still has vibes even when i put in a set of 3.23's.
the first time the tranny was apart was over the winter and after that is when they started, the front drum was wiped out, so now i have another new one in there and still now change
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 08:37 PM
Quote:
and this is an 8 3/4 rear?
yes it is
Posted By: ProSport
Re: vibration update on the cuda - 09/27/08 08:37 PM
Have you checked tire/wheel balance?
Posted By: tazmaniac
Re: vibration update on the cuda - 09/27/08 08:43 PM
How much endplay between convertor and flex plate, flexplate cracked?
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 08:44 PM
Quote:
Have you checked tire/wheel balance?
yup and even tried another set of tires and wheels
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 08:45 PM
Quote:
How much endplay between convertor and flex plate, flexplate cracked?
how much should there be? the converter slide right up to the flex plate with no issues. i looked at the flex plate and rechecked the TQ specs too, and no issues there.
Posted By: smokinwoody
Re: vibration update on the cuda - 09/27/08 08:47 PM
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and this is an 8 3/4 rear?
yes it is
and I take it you had the whole thing checked out..
weird man...all the components you had checked...yet usualy when a vibration takes out rear U joints would be...unbalanced drive shaft...bad u joints to begin with...bad pinion yoke or bearings to same...misalignment/..
if the axles were bad you would be eating gears and seals..
the suspension is all tight?...outside of installing a whole new drivetrain...got me hangin..
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 08:52 PM
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and this is an 8 3/4 rear?
yes it is
and I take it you had the whole thing checked out..
weird man...all the components you had checked...yet usualy when a vibration takes out rear U joints would be...unbalanced drive shaft...bad u joints to begin with...bad pinion yoke or bearings to same...misalignment/..
if the axles were bad you would be eating gears and seals..
the suspension is all tight?...outside of installing a whole new drivetrain...got me hangin..
i know, this has me totally lost. i tired my stock axles too lol, and it only eats the rear u joint never the front one. if i run down the track i might get 2 passes out of the rear u joint, SUX unless the rear housing is somehow bent and dont know what the leaf springs would do if they were bad, cruizing around town its smooth as glass, till i get to 80mph then it goes south
Posted By: PC-CHARGER
Re: vibration update on the cuda - 09/27/08 09:00 PM
Sounds like you've tried most everything. Some Mopars came from factory with a large damper weight bolted to the rear of the transmission tailshaft to counter some hamonic vibrations in the driveline. I can't say specifically which models it was on but maybe yours needs this? Here's a picture of one style. The tails shaft housing for this damper has two 5/16" UNC bolts holes tapped diretcly underneath the output seal.
Posted By: tazmaniac
Re: vibration update on the cuda - 09/27/08 09:01 PM
show have .100-.200 endplay should not be tight possible at higher speeds without some endplay convertor will push up against pump.
Posted By: MR_P_BODY
Re: vibration update on the cuda - 09/27/08 09:09 PM
Quote:
I cracked a second tailshaft housing 3 weeks ago. I'm finally ready to go tear it apart tomorrow. What I'm gonna do is drop 3 lines. One from the balancer, 1 from the trans tailshaft and one from the rear pinion yoke. Then gonna check it with a laser level to see where the line runs from front to back. I'm thinking on mine that I may be off side to side with my trans crossmember. Also, did you use a new crush sleeve when you swapped yokes? I didn't on mine and that is another thought I had. Maybe the pinion isn't set correctly creating the vibrations. But I'm not getting any groaning noises.
What I guess I'm asking here is, do you think that with all the times that you've had yours apart, that maybe the tailshaft isn't located exactly where it was before all this started, up/down & side to side ? When was the very time you took it apart for this problem? What was wrong then?
Cars and trucks are made with the pinion off-set
from the tail shaft to make sure the U-joint is
always working. But in racecars that I build I use
a laser mounted in the rear main of the block that
points directly on the pinion centerline then I
adjust the pinion angle to keep the U-joint working
Posted By: Cab_Burge
Re: vibration update on the cuda - 09/27/08 09:53 PM
It is time to start isolating the cause or causes. Jack the car up(both ends) and put it on jack stands again under the suspension so all the weight is on the jackstands like it is on the track. Run it in gear first to make sure where the vibrations start and stop, RPM or MPHs . Shut the motor off and remove the rear tires, put all of the lug nuts back on tght enough to hold the brake drums on and test it agian, if the vibration is still there remove the break drums next and test agian. If thats not it do the axles next and retest again. The last thing to test is removing the driveshaft and that will allow some fluid to leak out. If none of those cure it then it is in the remaining parts, converter, trans, engine and so on. Test, test and test some more
There is no magic in these parts, some problems are harder to diaignose than others
Please let us know how it goes and what you find. BTW, are you lubing the new U joints with a good Hi temp wheel bearing grease before installing them
If not do that next time and every time. U joints come with a rust preventive grese like cosmoleium (SP?) in them that is not intended to be ran on the road. I learn that the hard way
One other thing to check is the pinion yoke and U joint alignment to the center of the pinion shaft, I had one pinion yoke that would not center the U joint which made the drive shaft wobble a very small amount.
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 10:00 PM
Quote:
show have .100-.200 endplay should not be tight possible at higher speeds without some endplay convertor will push up against pump.
i definately had between .100 and .200 or end play
Posted By: Leigh
Re: vibration update on the cuda - 09/27/08 10:06 PM
Probably not it, but, my truck slowly developed a cyclical vibration as the original leaf srings lost ride height. The faster I went, the worse it got.
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 10:09 PM
Quote:
It is time to start isolating the cause or causes. Jack the car up(both ends) and put it on jack stands again under the suspension so all the weight is on the jackstands like it is on the track. Run it in gear first to make sure where the vibrations start and stop, RPM or MPHs . Shut the motor off and remove the rear tires, put all of the lug nuts back on tght enough to hold the brake drums on and test it agian, if the vibration is still there remove the break drums next and test agian. If thats not it do the axles next and retest again. The last thing to test is removing the driveshaft and that will allow some fluid to leak out. If none of those cure it then it is in the remaining parts, converter, trans, engine and so on. Test, test and test some more There is no magic in these parts, some problems are harder to diaignose than others Please let us know how it goes and what you find. BTW, are you lubing the new U joints with a good Hi temp wheel bearing grease before installing them If not do that next time and every time. U joints come with a rust preventive grese like cosmoleium (SP?) in them that is not intended to be ran on the road. I learn that the hard way One other thing to check is the pinion yoke and U joint alignment to the center of the pinion shaft, I had one pinion yoke that would not center the U joint which made the drive shaft wobble a very small amount.
, well 1st and second are smooth, in 3rd now with the car on stands i can feel a vibe at 35mph, i can feel this with my hand on the car, it comes and goes when i change rpms it will stop at certain speeds and rpms, then it will come back. At around 45 to 55 i dont feel it, the it starts to show up around 80. i dont see anything moving out of the ordinary. i measured the rear from side to side and the rear is 3/8" more to the passing side. if that matters or not., how bent would the rear housing have to be to cause this, or would it? i looked at the harmonic balancer and it doesnt even look like its moving, so i dont think theres an issue there, and the motor doesnt even look like its running thats how smooth it looks. if it was something thats not in or near the rear would it still cause only the rear ujoint to go bad. if it was something from the transmission tail shaft forward would it try to eat the front ujoint and not the rear. Im thinking its something in the back end cause it only eats the rear ujoint
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 10:10 PM
Quote:
Probably not it, but, my truck slowly developed a cyclical vibration as the original leaf srings lost ride height. The faster I went, the worse it got.
im not even sure how old my springs are, i've had the car for 7yrs now and there the same ones
Posted By: Leigh
Re: vibration update on the cuda - 09/27/08 10:17 PM
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Probably not it, but, my truck slowly developed a cyclical vibration as the original leaf srings lost ride height. The faster I went, the worse it got.
im not even sure how old my springs are, i've had the car for 7yrs now and there the same ones
Since you've run it on jack stands, probably not the cause.
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 10:25 PM
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Quote:
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Probably not it, but, my truck slowly developed a cyclical vibration as the original leaf srings lost ride height. The faster I went, the worse it got.
im not even sure how old my springs are, i've had the car for 7yrs now and there the same ones
Since you've run it on jack stands, probably not the cause.
lol wish full thinking
Posted By: Thumperdart
Re: vibration update on the cuda - 09/27/08 10:35 PM
I`ve chased my tail in the past just like you. 1`st thing I did after a drive and vibration check was, I checked to see at what RPM`S(and compared to mph for reference) the vibration occured NOT just the mph and then went home, put it in neutral and went to the rpm`s(mph) at which the vibrations occured to make sure it wasn`t MOTOR related. More times than not for me it has been engine harmonics not trans,d-shaft etc. If you run solid mounts it makes it even worse.
Posted By: MR_P_BODY
Re: vibration update on the cuda - 09/27/08 10:56 PM
well 1st and second are smooth, in 3rd now with the car on stands i can feel a vibe at 35mph, i can feel this with my hand on the car, it comes and goes when i change rpms it will stop at certain speeds and rpms, then it will come back. At around 45 to 55 i dont feel it, the it starts to show up around 80. i dont see anything moving out of the ordinary. i measured the rear from side to side and the rear is 3/8" more to the passing side. if that matters or not., how bent would the rear housing have to be to cause this, or would it? i looked at the harmonic balancer and it doesnt even look like its moving, so i dont think theres an issue there, and the motor doesnt even look like its running thats how smooth it looks. if it was something thats not in or near the rear would it still cause only the rear ujoint to go bad. if it was something from the transmission tail shaft forward would it try to eat the front ujoint and not the rear. Im thinking its something in the back end cause it only eats the rear ujoint
Since you've changed most everything I would have to
start looking at the engine. Since it comes and goes
its a frequency thats multipling. Most of the time
if its a problem with something thats on a centerline
such as a trans(all the items are balanced to a
centerline)the problem only gets worse with the higher
rpm, not coming and going. The engine can run into
frequecy issues, coming and going. I wish you could
un-bolt the converter and run the engine by itself
just to eliminate things. Dont be so sure about the
engine or trans taking out the front U-joint and
the rearend being the cause for rear U-joint failure,
cars do alot of funny things when something is going
in and out of frequency and can transmit it to
strange places
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 11:36 PM
Quote:
well 1st and second are smooth, in 3rd now with the car on stands i can feel a vibe at 35mph, i can feel this with my hand on the car, it comes and goes when i change rpms it will stop at certain speeds and rpms, then it will come back. At around 45 to 55 i dont feel it, the it starts to show up around 80. i dont see anything moving out of the ordinary. i measured the rear from side to side and the rear is 3/8" more to the passing side. if that matters or not., how bent would the rear housing have to be to cause this, or would it? i looked at the harmonic balancer and it doesnt even look like its moving, so i dont think theres an issue there, and the motor doesnt even look like its running thats how smooth it looks. if it was something thats not in or near the rear would it still cause only the rear ujoint to go bad. if it was something from the transmission tail shaft forward would it try to eat the front ujoint and not the rear. Im thinking its something in the back end cause it only eats the rear ujoint
Since you've changed most everything I would have to
start looking at the engine. Since it comes and goes
its a frequency thats multipling. Most of the time
if its a problem with something thats on a centerline
such as a trans(all the items are balanced to a
centerline)the problem only gets worse with the higher
rpm, not coming and going. The engine can run into
frequecy issues, coming and going. I wish you could
un-bolt the converter and run the engine by itself
just to eliminate things. Dont be so sure about the
engine or trans taking out the front U-joint and
the rearend being the cause for rear U-joint failure,
cars do alot of funny things when something is going
in and out of frequency and can transmit it to
strange places
when i had the motor redone 2yrs ago which just reringing it and new rod, main and cam bearing and oil pump, the motor was smooth as glass, which it feels now, when i put my hand on the car and can feel the vibes i dont feel it near the motor only from the door back i feel it, thats where its the strongest. i was holding my hands on the motor at 35 mph with rags and felt no vibes but when i walked around the side of the car and put my hand on the driver side rocker panel thats where i can feel it
Posted By: Thumperdart
Re: vibration update on the cuda - 09/27/08 11:39 PM
Like I said above in my post......by running it in the driveway you eliminate the DRIVING/MOVING variations out of the equation w/leaves motor or converter.....
Good luck........
Posted By: dartman366
Re: vibration update on the cuda - 09/27/08 11:45 PM
I see where you used three different driveshafts but did you have any one of them balanced by a machine shop?
are you absolutly sure the U joint fit's the rear yoke, had one on a car once that the U joint was a little narrower that the tab's in the yoke that center the U joint, and it was to one side more than the other and threw it off balance.
did you witness the rotation of the driveshaft when you had it on the stand's to make sure it was running true, I think total runout is supposed to be .010-.015 across the length of it.
that's all I can think of right now.
Posted By: Thumperdart
Re: vibration update on the cuda - 09/27/08 11:48 PM
I want to know how in the hell you can put your hand on the motor at 35 mph......must have a long arm.
Posted By: Michael
Re: vibration update on the cuda - 09/27/08 11:50 PM
U-joints are phased right????
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 11:55 PM
Quote:
I want to know how in the hell you can put your hand on the motor at 35 mph......must have a long arm.
ROFLAMO i had the car on jack stands in the garage and my wife was in the car
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 11:57 PM
Quote:
I see where you used three different driveshafts but did you have any one of them balanced by a machine shop?
are you absolutly sure the U joint fit's the rear yoke, had one on a car once that the U joint was a little narrower that the tab's in the yoke that center the U joint, and it was to one side more than the other and threw it off balance.
did you witness the rotation of the driveshaft when you had it on the stand's to make sure it was running true, I think total runout is supposed to be .010-.015 across the length of it.
that's all I can think of right now.
one of the D/S came right out of another car that had no issues with vibes., i did a runout on the D/S a few weeks back and at the worst point was .010. im running a presision (sp) u joint, and this fit by far the best out of all the other i tried
Posted By: cudadan
Re: vibration update on the cuda - 09/27/08 11:57 PM
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U-joints are phased right????
not sure what that means
Posted By: MR_P_BODY
Re: vibration update on the cuda - 09/28/08 12:14 AM
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U-joints are phased right????
not sure what that means
Meaning that each is lined up with the other, instead
of being clocked a little wrong.... but you have
had 3 different d-shafts in it so I would say that
you have eliminated that(still just guessing)
How bad of a viration is it at 80mph and what does
that translate to in rpm at the engine... its a
rpm issue and not a speed thing. I'm sure that if
you changed gears in the rear that the speed of the
vibration would change so its all about rpm of any
given component
Posted By: Chris'sBarracuda
Re: vibration update on the cuda - 09/28/08 12:19 AM
I'm thinking you have hit it right on Mike..
If he has changed gear ratios, but the vibration stays at 80mph, than it should be easier to narrow it down..
Chris..
Posted By: Anonymous
Re: vibration update on the cuda - 09/28/08 12:32 AM
did you check the front & rear wheels?
balanced or bent rim if seen cause it also at different tspeeds.
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 01:56 AM
Quote:
did you check the front & rear wheels?
balanced or bent rim if seen cause it also at different tspeeds.
it wouldnt be the front wheels cause i only had the real on the stands when i checked it, but i did also run it w/o the wheels and tires
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 01:58 AM
Quote:
I'm thinking you have hit it right on Mike..
If he has changed gear ratios, but the vibration stays at 80mph, than it should be easier to narrow it down..
Chris..
when i put the 3.23's in, the vibes were at about 110 mph, it just moved farther away
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 02:00 AM
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U-joints are phased right????
not sure what that means
Meaning that each is lined up with the other, instead
of being clocked a little wrong.... but you have
had 3 different d-shafts in it so I would say that
you have eliminated that(still just guessing)
How bad of a viration is it at 80mph and what does
that translate to in rpm at the engine... its a
rpm issue and not a speed thing. I'm sure that if
you changed gears in the rear that the speed of the
vibration would change so its all about rpm of any
given component
at 35 mph there not to bad but 80 ther real bad, i think the rpms are around 5200 at 80, this is with 4.30s
Posted By: MR_P_BODY
Re: vibration update on the cuda - 09/28/08 02:05 AM
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I'm thinking you have hit it right on Mike..
If he has changed gear ratios, but the vibration stays at 80mph, than it should be easier to narrow it down..
Chris..
when i put the 3.23's in, the vibes were at about 110 mph, it just moved farther away
This all relates back to a rpm, do you know what
the rpm's were for the 110 speed and the rpm's for
the 80 speed, does it corrilate to the difference
in gear ratio where the d-shaft is turning the same rpm?
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 02:11 AM
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I'm thinking you have hit it right on Mike..
If he has changed gear ratios, but the vibration stays at 80mph, than it should be easier to narrow it down..
Chris..
when i put the 3.23's in, the vibes were at about 110 mph, it just moved farther away
This all relates back to a rpm, do you know what
the rpm's were for the 110 speed and the rpm's for
the 80 speed, does it corrilate to the difference
in gear ratio where the d-shaft is turning the same rpm?
i cant remeber the rpms with the 3.23's , i'll get a better number with the 4.30s next time i take it out. but since i still have the vibes with both the 430s and the 323s, wouldnt that eliminate the gears?
Posted By: MR_P_BODY
Re: vibration update on the cuda - 09/28/08 02:24 AM
i cant remeber the rpms with the 3.23's , i'll get a better number with the 4.30s next time i take it out. but since i still have the vibes with both the 430s and the 323s, wouldnt that eliminate the gears?
Without thinking much, that tells me that IF the
2 ratio's have the same d-shaft rpm then the problem
is the d-shaft forward, eliminating the rear end
and its compotents
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 02:33 AM
Quote:
i cant remeber the rpms with the 3.23's , i'll get a better number with the 4.30s next time i take it out. but since i still have the vibes with both the 430s and the 323s, wouldnt that eliminate the gears?
Without thinking much, that tells me that IF the
2 ratio's have the same d-shaft rpm then the problem
is the d-shaft forward, eliminating the rear end
and its compotents
i think i agree with ya there, the only other part that i didnt change was the flex plate. it is a b&m externally balanced pc. i didnt see any cracks and it didnt look to be bent. the converter holes lined up perfect also
Posted By: Sledge_57
Re: vibration update on the cuda - 09/28/08 02:48 AM
You said:
Quote:
the first time the tranny was apart was over the winter and after that is when they started, the front drum was wiped out, so now i have another new one in there and still now change
I have a question now. Are you saying the problem started after the trans was put back together with a new front drum?
If so maybe the drum is bad and out of balance
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 02:56 AM
Quote:
You said:
Quote:
the first time the tranny was apart was over the winter and after that is when they started, the front drum was wiped out, so now i have another new one in there and still now change
I have a question now. Are you saying the problem started after the trans was put back together with a new front drum?
If so maybe the drum is bad and out of balance
yes and i replaced it with another drum to have the same affect
Posted By: Anonymous
Post deleted by Defbob - 09/28/08 03:59 AM
Posted By: dvw
Re: vibration update on the cuda - 09/28/08 12:52 PM
For what its worth I have the same problem with my 73 Challenger. The vibration is rpm related to driveshaft speed. This is why the speed which it occurs changes with gear ratio. I have changed,balanced,swapped the following. Rear pigs & ratios,axles,drums,wheels & tires,driveshafts,trans & engine mounts. The difference is mine is a 4 speed. I can push the clutch in and it still vibrates. My u-joint angles mirror each other +1.5,-1.5. The only part I haven't swapped is the transmision. My bellhousing is dialed in both on center and square to the crank within .005". Sounds very similar. My bet (though I've never seen it) is the problem lies inthe outputshaft/tailshaft area.
Doug
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 01:22 PM
Quote:
maybe the nut behind the wheel needs to be tightened
thats is Fred you don't get anymore pix with Andrea LMAO
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 01:24 PM
Quote:
For what its worth I have the same problem with my 73 Challenger. The vibration is rpm related to driveshaft speed. This is why the speed which it occurs changes with gear ratio. I have changed,balanced,swapped the following. Rear pigs & ratios,axles,drums,wheels & tires,driveshafts,trans & engine mounts. The difference is mine is a 4 speed. I can push the clutch in and it still vibrates. My u-joint angles mirror each other +1.5,-1.5. The only part I haven't swapped is the transmision. My bellhousing is dialed in both on center and square to the crank within .005". Sounds very similar. My bet (though I've never seen it) is the problem lies inthe outputshaft/tailshaft area.
Doug
do you still have this problem?
Posted By: GomangoCuda
Re: vibration update on the cuda - 09/28/08 01:42 PM
Quote:
i think the rpms are around 5200 at 80, this is with 4.30s
That can't be right unless your converter is slipping real bad or your tires are about 20" tall. Should be well over 100 MPH at 5200 rpm.
Quote:
the only other part that i didnt change was the flex plate. it is a b&m externally balanced pc. i didnt see any cracks and it didnt look to be bent. the converter holes lined up perfect also
Any chance it lost a balance weight?
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 02:34 PM
Quote:
Quote:
i think the rpms are around 5200 at 80, this is with 4.30s
That can't be right unless your converter is slipping real bad or your tires are about 20" tall. Should be well over 100 MPH at 5200 rpm.
Quote:
the only other part that i didnt change was the flex plate. it is a b&m externally balanced pc. i didnt see any cracks and it didnt look to be bent. the converter holes lined up perfect also
Any chance it lost a balance weight?
thats why i said i think lol there are no weights on the converter. i just got the converter back from getting a freshening up too
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 02:38 PM
im just hoping that its not the motor somehow
Posted By: MR_P_BODY
Re: vibration update on the cuda - 09/28/08 02:49 PM
lol there are no weights on the converter. i just got the converter back from getting a freshening up too
I thought the 360 converter had a weight welded
on it to compensate for the crank weight
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 03:22 PM
Quote:
lol there are no weights on the converter. i just got the converter back from getting a freshening up too
I thought the 360 converter had a weight welded
on it to compensate for the crank weight
the b&m flex plate takes car of that, it has a big half moon cut out of it
Posted By: B1HEAD_USER
Re: vibration update on the cuda - 09/28/08 04:07 PM
Are the input and output shaft in the trans the same or were they changed? I have a friend that had a vibration problem with his chevy. It turned out to be a slighly bent input shaft in the trans. Next time the trans is apart put the shafts between centers and check them.
Posted By: Anonymous
Re: vibration update on the cuda - 09/28/08 04:14 PM
That B&M flexplate cold be it, I've had problems with mine and other people on this site have too.
Posted By: JohnRR
Re: vibration update on the cuda - 09/28/08 04:20 PM
Quote:
Quote:
the only other part that i didnt change was the flex plate. it is a b&m externally balanced pc. i didnt see any cracks and it didnt look to be bent. the converter holes lined up perfect also
Any chance it lost a balance weight?
They don't add weight to them , they remove the required amount of weight 180* off from where you need to add the weight to get the desired result .
Posted By: JohnRR
Re: vibration update on the cuda - 09/28/08 04:20 PM
Quote:
That B&M flexplate cold be it, I've had problems with mine and other people on this site have too.
Good point Mike , I'd take the flexpalte to a machine shop and have it checked .
Posted By: DoctorDiff
Re: vibration update on the cuda - 09/28/08 04:36 PM
Why was the transmission rebuilt? Could be a bent main shaft.
Did you change the stock pinion angle? If so, how did you do it?
Posted By: dodgefarmer
Re: vibration update on the cuda - 09/28/08 04:37 PM
Bushing replaced in tailshaft housing? Also hows the tranny mount?
Randy
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 04:37 PM
the flex plate is my next try, just sux im gonna pull the trans again, but i am really getting good at it LOL
i really appreciate all the feed back guys
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 04:38 PM
Quote:
Are the input and output shaft in the trans the same or were they changed? I have a friend that had a vibration problem with his chevy. It turned out to be a slighly bent input shaft in the trans. Next time the trans is apart put the shafts between centers and check them.
they both have been changed, the only thing thats the same is the housing itself, even changed the tail housing
Posted By: Bad340fish
Re: vibration update on the cuda - 09/28/08 05:05 PM
Bust your u-bolts loose and check the spring perches. I had one come loose on mine. After putting in a new driveshaft and fixing the sprag I drove the car and it drove like crap. However, everything passed the visual check. The weld had a hairline on it that didn't look like anything. Removing the u-bolts showed it was busted completly loose from the housing. Could be your pinion angle is going wild when going down the road, and returns to normal when under no load(due to a busted perch).
Would be an easy check before pulling the trans.
Posted By: 493_Scamp
Re: vibration update on the cuda - 09/28/08 05:24 PM
I would run it without a shaft.Make a dummy plug out of an old yoke and a plate to keep it from backing out. Run the car at the rpm it vibrates and shift 2-3 a couple times.Remember not to hit park,just shut it off. What happened to the original front drum? Did the bushings and washers look ok? Hows the end play?
Posted By: blown360
Re: vibration update on the cuda - 09/28/08 05:54 PM
Had a problem like this on a foden truck over here once.it would get bad vibration over 40 mph.Checked everything and finally found it to be a bent axle casing.
Posted By: cudadan
Re: vibration update on the cuda - 09/28/08 11:50 PM
Quote:
I would run it without a shaft.Make a dummy plug out of an old yoke and a plate to keep it from backing out. Run the car at the rpm it vibrates and shift 2-3 a couple times.Remember not to hit park,just shut it off. What happened to the original front drum? Did the bushings and washers look ok? Hows the end play?
thats actaully a good idea there, the front drum was in bad shape and couldnt be reused, end play is all good
Posted By: lowell66dart
Re: vibration update on the cuda - 09/29/08 12:19 AM
If you do pull the tranny bolt the converter back up and check the runout with a dial indicator. I have a B&M flexplate on my 340 that I had to modify to work. Won't buy another one.
Posted By: rowin4
Re: vibration update on the cuda - 09/29/08 01:35 AM
Just my
as every body else has a cure to your problem. You say that you get two runs before the rear joint goes bad? I would think if it was in the trans the front joint would go. I would look at the rear pinion angle , the rear housing is probably sticking straight up. U-joints can take alot of vibes before they wear out. Also look at the rear yoke to see if it's spread out , if it is, it won't center and cause a vibe and even kick out the joint.
Posted By: cudadan
Re: vibration update on the cuda - 09/29/08 01:41 AM
Quote:
If you do pull the tranny bolt the converter back up and check the runout with a dial indicator. I have a B&M flexplate on my 340 that I had to modify to work. Won't buy another one.
but the flex plate was workn before with no issue could it just go bad?
Posted By: cudadan
Re: vibration update on the cuda - 09/29/08 01:44 AM
Quote:
Just my as every body else has a cure to your problem. You say that you get two runs before the rear joint goes bad? I would think if it was in the trans the front joint would go. I would look at the rear pinion angle , the rear housing is probably sticking straight up. U-joints can take alot of vibes before they wear out. Also look at the rear yoke to see if it's spread out , if it is, it won't center and cause a vibe and even kick out the joint.
but the angle was good before this problem started ive changed the angle up abd down a few degree's all still with the same results
Posted By: rowin4
Re: vibration update on the cuda - 09/29/08 02:18 AM
I would look at the angle again and definetly look at the spread of the yoke to see if the joint fits tight between the tabs. Is the joint kicking out of the rear yoke or has it?
Posted By: moretoys
Re: vibration update on the cuda - 09/29/08 03:12 AM
Stock trans mount/height??solid/poly mount??
Maybe the rear axle housing bent.any problems sliding the axles in/out??
Posible bent spring/making thrust angle off.rear wheels pointing more 1 way then the other.(dog tracking)
Do you buzz the engine to the same rpm in 1st and 2nd??
Switching to 3.23 gears made the vibration come at a higher mph,Then It has to be rpm related
A shot in the dark.the fan???
A cracked flywheel will usually make some noises
tailshaft bushings ok??
Vibrations can travel.What if the vibration is up front of the shaft,but the rear u-joints go bad because there is no room to move/ more tightly held together.
Have you had it on jackstand,and whatched the driveshaft,should be pretty smooth,any osilation.
just thinking outloud.
Posted By: JohnRR
Re: vibration update on the cuda - 09/29/08 03:16 AM
Quote:
Quote:
If you do pull the tranny bolt the converter back up and check the runout with a dial indicator. I have a B&M flexplate on my 340 that I had to modify to work. Won't buy another one.
but the flex plate was workn before with no issue could it just go bad?
If the flexplate was in before this and was ok it would still be fine, there are no extra weights on it unless you put some extra holes in it for some strange reason.
what happened to the front drum ?
Posted By: moper
Re: vibration update on the cuda - 09/29/08 04:32 PM
How are you sintalling teh u joints? Are you seating them against the clips after installing the clips? It's driveshaft. Definately. If you moved it up and fdowna couple degrees (pinion angle) what is is currently set at? You are positive you're measuring it properly?
Posted By: cudadan
Re: vibration update on the cuda - 09/29/08 10:45 PM
Quote:
How are you sintalling teh u joints? Are you seating them against the clips after installing the clips? It's driveshaft. Definately. If you moved it up and fdowna couple degrees (pinion angle) what is is currently set at? You are positive you're measuring it properly?
im using a vise to put them in and pushing them up against the clips too. for a few yrs i was running at 5.7 down with no problem, then i moved it up a degree at a time to 2.7 and all still had the same results. im gonna order a brand new yoke just so i can eliminate that
Posted By: cudadan
Re: vibration update on the cuda - 09/29/08 11:19 PM
Quote:
Stock trans mount/height??solid/poly mount??
Maybe the rear axle housing bent.any problems sliding the axles in/out?? axles go in great
Posible bent spring/making thrust angle off.rear wheels pointing more 1 way then the other.(dog tracking) not sure
Do you buzz the engine to the same rpm in 1st and 2nd?? yes and no vibes
Switching to 3.23 gears made the vibration come at a higher mph,Then It has to be rpm related
A shot in the dark.the fan??? electric
A cracked flywheel will usually make some noises
tailshaft bushings ok?? new tailshaft,housing and bushing
Vibrations can travel.What if the vibration is up front of the shaft,but the rear u-joints go bad because there is no room to move/ more tightly held together.
Have you had it on jackstand,and whatched the driveshaft,should be pretty smooth,any osilation.
just thinking outloud.
, did that the other day, and everything spins so smooth that it doesn't look like its moving
Posted By: dartman366
Re: vibration update on the cuda - 09/29/08 11:31 PM
I say just give it up and I will come over with my trailer and get it out of your hair and you wont have the problem any more,,,,,,,whatta' ya' think???
J/K hope you sort it out, but i'm outta thought's.
Posted By: cudadan
Re: vibration update on the cuda - 09/29/08 11:32 PM
Quote:
I say just give it up and I will come over with my trailer and get it out of your hair and you wont have the problem any more,,,,,,,whatta' ya' think???
pleeeeeease come and take it LOL hey and its a real 74 360 cuda too lol
J/K hope you sort it out, but i'm outta thought's.
Posted By: MR_P_BODY
Re: vibration update on the cuda - 09/29/08 11:48 PM
I would think your next step would be to take the
d-shaft out and put a slip yoke in the trans and
mount something to to keep it from falling out.
Spin it up to the known problem rpm/speed and see
if its still there, that would emininate the d-shaft
and rear end if its still there..... or it would
say that its a d-shaft or rear end problem if it
isnt there
Posted By: boomer
Re: vibration update on the cuda - 09/29/08 11:53 PM
Somebody before mentioned loosening the U-bolts to check springs. If you do that, also check for a twisted axle tube at the housing. I have seen this before and it didn't cause any issues except for bad vibrations at different speeds (harmonics will cause vibrations to come and go when they hit like frequencies). You have eliminated everything else except for the rear end housing itself, I think that is where I would be looking next.....
Posted By: Anonymous
Post deleted by Defbob - 09/30/08 01:12 AM
Posted By: MoparDonny
Re: vibration update on the cuda - 09/30/08 02:45 AM
Dan, my challenger was doing the same thing. Had the shaft balanced and new u-joints, same prob. Changed the mount cause it was kinda sacked anyway, same prob. Then when my Dad had his new driveshaft made i thought I'd swap his old one in to see if it was any different. It was 5/8 of an inch longer than mine. Cured 80-90 percent of the problem. The resulting damaged tailhousing bushing could be the last little bit.
I'm gonna change the bushing sometime this winter so I'll know in the spring if it helped. Hope you get yours figured out sooner than that!! Ha ha!!
Don.
Posted By: GEORGE68HEMIRR
Re: vibration update on the cuda - 10/01/08 12:45 AM
Dan....had same problem....i went nuts checking everything and it turned out to be the damper....ATI super damper was puking out the o-rings which looked funky on the front of the damper.....sent it back for rebuild....$75.00....problem went away....that was too easy
Posted By: flatiron
Re: vibration update on the cuda - 10/01/08 11:39 AM
Quote:
I would think your next step would be to take the
d-shaft out and put a slip yoke in the trans and
mount something to to keep it from falling out.
Spin it up to the known problem rpm/speed and see
if its still there, that would emininate the d-shaft
and rear end if its still there..... or it would
say that its a d-shaft or rear end problem if it
isnt there
I'm having the same problem and I was wondering about doing this. But I have 2 questions How would you keep the slip yoke on the tailshaft? Will it hurt the engine/tranny running it up to 5500 with no load on it?
Posted By: wheelsup68dart
Re: vibration update on the cuda - 10/01/08 12:09 PM
Put a 2.74 gear in it and you won't reach the MPH necessary to cause vibration
. I agree with many other that it sounds like pinion angle to me, Do as suggested and check to make sure the spring perchs are good and not cracked form housing. Could still be a balance problem with the engine somehow. If the B+M flexplate is supposed to be balanced for 360 and the converter people no the converter is going in a 360. The converter may not be neutral balanced and could also be balanced for 360.
I would think if both these items were balanced for 360 you would get an out of balance effect.
Posted By: flatiron
Re: vibration update on the cuda - 10/01/08 12:48 PM
Quote:
Quote:
I would think your next step would be to take the
d-shaft out and put a slip yoke in the trans and
mount something to to keep it from falling out.
Spin it up to the known problem rpm/speed and see
if its still there, that would emininate the d-shaft
and rear end if its still there..... or it would
say that its a d-shaft or rear end problem if it
isnt there
I'm having the same problem and I was wondering about doing this. But I have 2 questions How would you keep the slip yoke on the tailshaft? Will it hurt the engine/tranny running it up to 5500 with no load on it?
Posted By: MR_P_BODY
Re: vibration update on the cuda - 10/01/08 01:05 PM
I'm having the same problem and I was wondering about doing this. But I have 2 questions How would you keep the slip yoke on the tailshaft? Will it hurt the engine/tranny running it up to 5500 with no load on it?
What I would do is have the car on stands and yoke
in the trans put a jack stand or something like it
with a flat plate mounted to the stand. Slide the
stand in behind the yoke just so its not touching,
so the yoke can move some. Run the car to the speed/rpm
thats the problem point.At least at this point you
could say its there(vib) and know that its a trans/engine
issue or no the vib issnt there and that would say
that its a d-shaft rear end problem. Running the
engine and trans isnt a problem with no load but
when you slow it down put it in N and shut the engine
off, dont put it in park with the engine running
Posted By: dvw
Re: vibration update on the cuda - 10/01/08 05:00 PM
Yes for what its worth my Challenger still has the problem. I haven't seen this question asked. What happens if it is put into nuetral above the vibration speed and is allowed to coast back down thru the vibration speed? Mine still shakes regardless if its in neutral or the clutch is disengaged. I was going to try engine off in neutral so the counter shaft and input shaft would not spin. The car is currently in storage.
An engine vibration doesn't have to have the vehicle moving to show up. That would eliminate from the convertor forward if it does not happen with the car at rest. Did I miss something? also when I installed a 2.76 chuck the vibration speed went over 100 mph.
Doug
Posted By: cudadan
Re: vibration update on the cuda - 10/01/08 09:38 PM
had the car out yesterday at around 60pmh, and i could feel it, i put the car in neutral and the vibes were still there until it slowed down below 40. now if i go out on the highway get it up to where its real bad, shut the engine off and coast, if it still has the vibes , im guessing it wouldnt be from the motor right?
Posted By: Anonymous
Post deleted by Defbob - 10/01/08 10:05 PM
Posted By: dannysbee
Re: vibration update on the cuda - 10/01/08 10:13 PM
It has to be the drive shaft that is why it moved up in speed when you changed to the cruiser rear gear. The yokes may be slightly out of align. I would put a whole different drive shaft in it.
Its not the engine or you could bring the engine up to the rpm it vibrates at setting still and you would feel it. Its the drive shaft.
Posted By: cudadan
Re: vibration update on the cuda - 10/01/08 10:16 PM
Quote:
It has to be the drive shaft that is why it moved up in speed when you changed to the cruiser rear gear. The yokes may be slightly out of align. I would put a whole different drive shaft in it.
just a vibration noise thats it. My brain is so fried right now Fred LOL. i'n gonna send the D/s thats in my car to the shop and see if its in specs, i've tried 3 and cant imagine they were all bad, but i wanna know for sure
Posted By: cudadan
Re: vibration update on the cuda - 10/01/08 10:47 PM
Quote:
Put a 2.74 gear in it and you won't reach the MPH necessary to cause vibration . I agree with many other that it sounds like pinion angle to me, Do as suggested and check to make sure the spring perchs are good and not cracked form housing. Could still be a balance problem with the engine somehow. If the B+M flexplate is supposed to be balanced for 360 and the converter people no the converter is going in a 360. The converter may not be neutral balanced and could also be balanced for 360. I would think if both these items were balanced for 360 you would get an out of balance effect.
just had the conveter redone to zero balance
Posted By: Bad340fish
Re: vibration update on the cuda - 10/01/08 11:05 PM
Ok Dan, get you a tow strap. Remove the driveshaft, tie strap to car, tie other end to truck. Have someone drive you up to speed and see if the vibe is still there. If its still there continue to tow the car to the highest point possible and push it off(be sure to unhook from truck) LOL j/k.
I hate vibrations, my jeep is double the fun as it has two driveshafts with double cardan joints, so 6 u-joints and 2 slips yokes spinning at all times can be fun when you get a vibe.
Posted By: wheelsup68dart
Re: vibration update on the cuda - 10/01/08 11:19 PM
Quote:
Quote:
Put a 2.74 gear in it and you won't reach the MPH necessary to cause vibration . I agree with many other that it sounds like pinion angle to me, Do as suggested and check to make sure the spring perchs are good and not cracked form housing. Could still be a balance problem with the engine somehow. If the B+M flexplate is supposed to be balanced for 360 and the converter people no the converter is going in a 360. The converter may not be neutral balanced and could also be balanced for 360. I would think if both these items were balanced for 360 you would get an out of balance effect.
just had the conveter redone to zero balance
Had it redone to zero balance?????? So it was a 360 balanced converter b4?? I agree with Fred, seldom do I read old threads form the beginning but I did this one and my Brain hurts. I agree with removing the driveshaft and towing it behind another vehicle. My continued thought at this point is pinion angle or broken spring perch. Please advise all on the board how you are adjusting/reading your current pinion angle and what the current reading is.
Posted By: cudadan
Re: vibration update on the cuda - 10/01/08 11:20 PM
Quote:
Ok Dan, get you a tow strap. Remove the driveshaft, tie strap to car, tie other end to truck. Have someone drive you up to speed and see if the vibe is still there. If its still there continue to tow the car to the highest point possible and push it off(be sure to unhook from truck) LOL j/k.
I hate vibrations, my jeep is double the fun as it has two driveshafts with double cardan joints, so 6 u-joints and 2 slips yokes spinning at all times can be fun when you get a vibe.
LOL i was thinking of a car dolly, but i'd be real affraid to go that fast LOL.
Posted By: MR_P_BODY
Re: vibration update on the cuda - 10/01/08 11:44 PM
LOL i was thinking of a car dolly, but i'd be real affraid to go that fast LOL.
Well if you dont want to drag it that fast you
better do what I suggested on the stands, either
way it would eliminate alot of stuff and zero in
on the problem
Posted By: cudadan
Re: vibration update on the cuda - 10/01/08 11:46 PM
Quote:
LOL i was thinking of a car dolly, but i'd be real affraid to go that fast LOL.
Well if you dont want to drag it that fast you
better do what I suggested on the stands, either
way it would eliminate alot of stuff and zero in
on the problem
im gonna try that first cause its easier lol
Posted By: Anonymous
Post deleted by Defbob - 10/01/08 11:59 PM
Posted By: cudadan
Re: vibration update on the cuda - 10/02/08 12:44 AM
LOL i dont wanna jinx anybody with this
Posted By: Sport440
Re: vibration update on the cuda - 10/02/08 12:44 AM
Quote:
Quote:
How are you sintalling teh u joints? Are you seating them against the clips after installing the clips? It's driveshaft. Definately. If you moved it up and fdowna couple degrees (pinion angle) what is is currently set at? You are positive you're measuring it properly?
im using a vise to put them in and pushing them up against the clips too.
There are 4 clips to align the u joint 2 that retain the joint in the shaft.
And 2 that position the joint in the pinion yoke. Some people discard these, do you still have yours? They are needed as they properly position/align the joint into the pinion yoke.
You also stated you did Not replace the crush sleeve when you did the gear change. If you grab the pinion yoke can you force any up or down play out of it, or is it tight.
On the front yoke you stated you had plenty of clearence. How much is plenty, if you have to much that can cause vibration too. After bottoming out the slip yoke I like about 1/2 to 3/4 of a inch clearence. 1" would be max IMO
Also what happend with you putting that thing on stands and running with no shaft and a slip yoke plug. On sunday you said that was a great idea and would try that.
But today you take it out for another cruise only to confirm the vibration, again!! 
I too think its related to the shaft or its componets. When you did the shaft run out was it installed on the car or on v blocks.
You will get her figured out, because you have alot heads working on it . mike
Posted By: cudadan
Re: vibration update on the cuda - 10/02/08 12:54 AM
Quote:
Quote:
Quote:
How are you sintalling teh u joints? Are you seating them against the clips after installing the clips? It's driveshaft. Definately. If you moved it up and fdowna couple degrees (pinion angle) what is is currently set at? You are positive you're measuring it properly?
im using a vise to put them in and pushing them up against the clips too.
There are 4 clips to align the u joint 2 that retain the joint in the shaft.
And 2 that position the joint in the pinion yoke. Some people discard these, do you still have yours? They are needed as they properly position/align the joint into the pinion yoke.
You also stated you did Not replace the crush sleeve when you did the gear change. If you grab the pinion yoke can you force any up or down play out of it, or is it tight.
On the front yoke you stated you had plenty of clearence. How much is plenty, if you have to much that can cause vibration too. After bottoming out the slip yoke I like about 1/2 to 3/4 of a inch clearence. 1" would be max IMO
Also what happend with you putting that thing on stands and running with no shaft and a slip yoke plug. On sunday you said that was a great idea and would try that.
But today you take it out for another cruise only to confirm the vibration, again!!
I too think its related to the shaft or its componets. When you did the shaft run out was it installed on the car or on v blocks.
You will get her figured out, because you have alot heads working on it . mike
i do have the clips in the ujoint all the way around, i have a max of 3/4 clearance, i didnt get a chance to spin it on the stands with just the yoke in the tail shaft cause i had to work. im gonna do my best to try it tomorrow after work, cause friday,sat and sun i'll be camping in the pocono's lol
Posted By: cudadan
Re: vibration update on the cuda - 10/03/08 12:49 PM
Quote:
I'm having the same problem and I was wondering about doing this. But I have 2 questions How would you keep the slip yoke on the tailshaft? Will it hurt the engine/tranny running it up to 5500 with no load on it?
What I would do is have the car on stands and yoke
in the trans put a jack stand or something like it
with a flat plate mounted to the stand. Slide the
stand in behind the yoke just so its not touching,
so the yoke can move some. Run the car to the speed/rpm
thats the problem point.At least at this point you
could say its there(vib) and know that its a trans/engine
issue or no the vib issnt there and that would say
that its a d-shaft rear end problem. Running the
engine and trans isnt a problem with no load but
when you slow it down put it in N and shut the engine
off, dont put it in park with the engine running
im gonna give this a shot when i get back on sunday, i'll let you guys know what happens,
thx again for the replys guys
Posted By: Anonymous
Post deleted by Defbob - 10/03/08 12:51 PM
Posted By: cudadan
Re: vibration update on the cuda - 10/03/08 01:17 PM
LOL i'll be hoping for good ones
Posted By: cudadan
Re: vibration update on the cuda - 10/06/08 09:42 PM
well i took the D/S out and put in a slip yoke, put a block of wood behind it, and ran it through the gears and no vibes at all, smooth as glass. so now its back to the D/S back. now since i changed everything there is where do i start? do i start changing everything all over again? i am gonna look at the pearches to make sure there are no cracks. i do have anew tranny mount that im gonna put it just for the hell of it too
Posted By: Bad340fish
Re: vibration update on the cuda - 10/06/08 10:43 PM
I would take the shaft into a driveshaft shop and have them check it out completly, then I would take it to another one and get a 2nd opinion.
Posted By: Anonymous
Post deleted by Defbob - 10/06/08 10:53 PM
Posted By: cudadan
Re: vibration update on the cuda - 10/06/08 11:17 PM
Quote:
Dan Tony Gambardella did my shafts and are fine
whats he charge over there, i've gotten ptices from everyone and the prices are all over the place lol
Posted By: DJVCuda
Re: vibration update on the cuda - 10/06/08 11:55 PM
well you can narrow it down to the drive shaft, rear or springs.
you said you never touched the springs....right?
Posted By: cudadan
Re: vibration update on the cuda - 10/07/08 12:00 AM
Quote:
well you can narrow it down to the drive shaft, rear or springs.
you said you never touched the springs....right?
yeah never touched'em, i put the pinion angle back down to 5.7 down cause thats where its always been. took it out for a ride and i still feel the vibes, even with a new tranny mount too. i'd go with super stock springs but i don't want my car to look likes it ready to go off road cause how high they sit lol, im gonna sand blast my other rear housing and put that in when i get a chance, maybe it could be bent or something.
Posted By: Al_Alguire
Re: vibration update on the cuda - 10/07/08 05:49 AM
I would just junk the shaft you have and buy a new one from a reputable builder...But what do I know
Posted By: cudadan
Re: vibration update on the cuda - 10/07/08 11:49 AM
one thing i did notice when i put the drive shaft back in there was a bout .010 to .015 side to side play where theu joint sits in the yoke.
Posted By: KatFysh
Re: vibration update on the cuda - 10/08/08 10:49 PM
Posted By: Anonymous
Post deleted by Defbob - 10/08/08 11:30 PM
Posted By: Leigh
Re: vibration update on the cuda - 10/08/08 11:41 PM
Posted By: cudadan
Re: vibration update on the cuda - 10/10/08 02:20 AM
Quote:
Look Here for a driveshaft
just got my new chromoly yoke today, i'll have it in tomorrow, then it's driveshaft time
Posted By: cudadan
Re: vibration update on the cuda - 10/11/08 01:10 AM
well still has the vibes with the brand new yoke, guess its time to try another driveshaft, almsot forgot how many i've tried in the car lol, or i might just put a whole other rear housing in first, that wont cost me anything
Posted By: MoparDonny
Re: vibration update on the cuda - 10/11/08 01:54 AM
How deep is the yoke into the trans and is the rear bushing tight? My driveshaft was 5/8 of an inch or so too short and it vibrated quite bad in the same fashion as you describe.
Don.
Posted By: cudadan
Re: vibration update on the cuda - 10/11/08 11:11 PM
Quote:
How deep is the yoke into the trans and is the rear bushing tight? My driveshaft was 5/8 of an inch or so too short and it vibrated quite bad in the same fashion as you describe.
Don.
the drive shaft that i was first using was in there for 6yrs with no issues, im gonna have one of the driveshafts checked out next week
Posted By: cudadan
Re: vibration update on the cuda - 11/22/08 10:45 PM
well i still have this issue with the vibes. how can i tell if the driveshaft is centered in the car or is it supposed to be to one side of the car more than the other? i measured from the side of the D/S to the frame on both sides and got a 2" difference, not sure if its supposed to be the same, any ideas? also i tried another driveshaft again with the same results. then i tried another center same results. i tested these with out the axles in the car, so i can eliminate all that, and still has vibes at 35mph but in reverse at the same rpm as forward there are no vibes at all smooth as glass
Posted By: rowin4
Re: vibration update on the cuda - 11/23/08 08:40 AM
Quote:
one thing i did notice when i put the drive shaft back in there was a bout .010 to .015 side to side play where theu joint sits in the yoke.
I mensioned that you should check the rear yoke for spreading [ twice ] on page three, Why are you changing out the front yoke if its destroying the rear u-joint??? There's probably more slop than that also.You might want to try turning thr rear yoke by hand to see if the pinion goes in and out some , if it does it might be the reason it doesen't vibe in reverse
Posted By: cudadan
Re: vibration update on the cuda - 11/23/08 02:11 PM
Quote:
Quote:
one thing i did notice when i put the drive shaft back in there was a bout .010 to .015 side to side play where theu joint sits in the yoke.
I mensioned that you should check the rear yoke for spreading [ twice ] on page three, Why are you changing out the front yoke if its destroying the rear u-joint??? There's probably more slop than that also.You might want to try turning thr rear yoke by hand to see if the pinion goes in and out some , if it does it might be the reason it doesen't vibe in reverse
i did put a new billtet yoke on the rear and the ujoint is a nice tight fit now, as for the rear it self i tried another set of gears, this set is a 3.91 with the same results as the 4.30's and the 3.23's
Posted By: Quicktree
Re: vibration update on the cuda - 11/23/08 03:05 PM
I had a customers duster that had a vibration problem years ago. I ended up changing all the simple stuff first. changed the tail shaft bushing, output shaft, yokes, ujoints, had the drive shaft balanced. nothing helped. I finally put one of my transmissions in it and the problem was gone. I tore down the tranyy and couldn't see anything wrong
Posted By: cudadan
Re: vibration update on the cuda - 11/23/08 03:58 PM
Quote:
I had a customers duster that had a vibration problem years ago. I ended up changing all the simple stuff first. changed the tail shaft bushing, output shaft, yokes, ujoints, had the drive shaft balanced. nothing helped. I finally put one of my transmissions in it and the problem was gone. I tore down the tranyy and couldn't see anything wrong
I hear ya there and tried all that too lol, the only left from my other tranny is the valve body, everything else is different, a problem like this makes me wanna sell the car lol
Posted By: PC-CHARGER
Re: vibration update on the cuda - 11/23/08 04:11 PM
Have you considered trying a factory damper that is attached to the tail housing?
Posted By: cudadan
Re: vibration update on the cuda - 11/23/08 04:50 PM
Quote:
Have you considered trying a factory damper that is attached to the tail housing?
, it wouldn't hurt to try something like that, but the only thing is something has cause this, and im affraid to race incase something lets go on the track
Posted By: cudadan
Re: vibration update on the cuda - 11/25/08 12:43 PM
and it still does this vibration, only in 3rd gear even after another trans
Posted By: sleepyhead416
Re: vibration update on the cuda - 11/25/08 02:05 PM
Dan I would be looken for a set of S/S springs. I've had them on my AAR & my Hemi R/T neither car sat high I dont like that look either the front spring bracket has holes to adjust height. Are your rear springs 24 years old ????? I still think it's a pinion angle problem thats why your u-joint don't last.
Posted By: WilliamHall
Re: vibration update on the cuda - 11/25/08 08:51 PM
I am guessing its the transmission. To me its simple, you changed the transmission and it started happening.
Posted By: cudadan
Re: vibration update on the cuda - 11/26/08 12:36 AM
Quote:
I am guessing its the transmission. To me its simple, you changed the transmission and it started happening.
but i pulled the trans pull all NEW internals in it and tail housing, the only thing that is still the same is the valve body and the housing itself. maybe if the housing has a lil crack that isnt noticable
Posted By: Anonymous
Post deleted by Defbob - 11/26/08 01:48 AM
Posted By: cudadan
Re: vibration update on the cuda - 11/26/08 02:08 AM
Quote:
LMAO its alomst there Fred
Posted By: SomeCarGuy
Re: vibration update on the cuda - 11/26/08 05:06 AM
Try a whole new trans.
There must be something off in that case. Maybe just a few thousandths or something, but something is wrong.
Or the rear end housing is bent.
Posted By: Anonymous
Post deleted by Defbob - 11/26/08 05:14 AM
Posted By: boomer
Re: vibration update on the cuda - 11/26/08 10:36 AM
Posted 2 months ago on this thread to check rear end housing. Everything else has either been checked or replaced EXCEPT for the housing.......
Change it.
Posted By: Quicktree
Re: vibration update on the cuda - 11/26/08 10:38 AM
Quote:
Try a whole new trans.
There must be something off in that case. Maybe just a few thousandths or something, but something is wrong.
Or the rear end housing is bent.
Posted By: cudadan
Re: vibration update on the cuda - 11/26/08 12:54 PM
Quote:
Posted 2 months ago on this thread to check rear end housing. Everything else has either been checked or replaced EXCEPT for the housing....... Change it.
i tried running it in 3rd gear WITHOUT the axles in the rear, so the only thing spinning is the gears
Posted By: WilliamHall
Re: vibration update on the cuda - 11/26/08 05:43 PM
Quote:
Quote:
Posted 2 months ago on this thread to check rear end housing. Everything else has either been checked or replaced EXCEPT for the housing....... Change it.
i tried running it in 3rd gear WITHOUT the axles in the rear, so the only thing spinning is the gears
I would just find it too concidental that this vibration would happen from something in the rear as soon as he changed the transmission. Its a possibility but I doubt it. Borrowing a known good transmission would be my first choice in this hard to solve problem.
Posted By: cudadan
Re: vibration update on the cuda - 11/26/08 05:48 PM
Quote:
Quote:
Quote:
Posted 2 months ago on this thread to check rear end housing. Everything else has either been checked or replaced EXCEPT for the housing....... Change it.
i tried running it in 3rd gear WITHOUT the axles in the rear, so the only thing spinning is the gears
I would just find it too concidental that this vibration would happen from something in the rear as soon as he changed the transmission. Its a possibility but I doubt it. Borrowing a known good transmission would be my first choice in this hard to solve problem.
thats what im trying to do now, just they are getting harder and harder to find. any locl\al guys have one i can borrow? LMAO
Posted By: dannysbee
Re: vibration update on the cuda - 11/26/08 06:28 PM
I need your address so I can send you a five dollar bill. That should cover the expences.
Posted By: cudadan
Re: vibration update on the cuda - 11/26/08 10:05 PM
well i located a trans and im picking it up this friday so by saturday morning i know if its the transmission, dam n i hope so
Posted By: cold85
Re: vibration update on the cuda - 11/26/08 10:27 PM
I am watching this thread I have the same problem with my charger I have changed real axles new wheels new 5-speed trans with new alum driveshaft and I still have a vibration.
Posted By: flatiron
Re: vibration update on the cuda - 11/26/08 11:13 PM
I know exactly what your going thru. I had almost the same post on here this past summer for my 67 Coronet. Same symptons tried alot of the easier stuff. Nothing I did made a change. Never got it on the strip like I planned now it's in storage till next spring and I get to spend the winter scratching my head about it. Looking forward to seeing your out come may be get me pointed in the right direction.
Posted By: cudadan
Re: vibration update on the cuda - 11/26/08 11:53 PM
i swear im losing sleep over this, i just can't believe how long ive had this problem., just hopefully when i try this other trans it goes away, i need to race LOL
Posted By: 70challenger408
Re: vibration update on the cuda - 11/27/08 09:21 AM
dan, I posted with the same problem on my challenger this past summer. I have changed every thing from the flex plate back, with the same results as you. The only thing left is the rear diff housing. I was looking for Santa to leave a new Moser housing under the tree this year LMAO.
scott
Posted By: cudadan
Re: vibration update on the cuda - 11/27/08 03:02 PM
Quote:
dan, I posted with the same problem on my challenger this past summer. I have changed every thing from the flex plate back, with the same results as you. The only thing left is the rear diff housing. I was looking for Santa to leave a new Moser housing under the tree this year LMAO.
scott
LMAO well if this other trans doesnt do it, i have another housing thats getting powerder coated next week, but i dont really think its the housing if it still has the vibes without the axels in it on the jack stands, still gonna change it anyway, i also measured the wheel base the other day and there was only 1/8" of a difference between sides.
Posted By: scatpacktom
Re: vibration update on the cuda - 11/27/08 03:07 PM
I hope the trans works for you Dan and all your questions get answered.
Posted By: cudadan
Re: vibration update on the cuda - 11/27/08 03:17 PM
Quote:
I hope the trans works for you Dan and all your questions get answered.
you and me both, lol thx again to everyone for all there help.
Posted By: flatiron
Re: vibration update on the cuda - 11/27/08 04:07 PM
Quote:
i swear im losing sleep over this, i just can't believe how long ive had this problem., just hopefully when i try this other trans it goes away, i need to race LOL
I'm just curious have you ran this car down the strip while this problem's been going on. I'm half scared to drive mine.
Posted By: sickhemi
Re: vibration update on the cuda - 11/27/08 06:04 PM
i think it's the output shaft. any chance you had two bent ones? when you changed the driveshaft did you use the same front yoke or did you use a different one?
Posted By: cudadan
Re: vibration update on the cuda - 11/28/08 03:40 AM
Quote:
Quote:
i swear im losing sleep over this, i just can't believe how long ive had this problem., just hopefully when i try this other trans it goes away, i need to race LOL
I'm just curious have you ran this car down the strip while this problem's been going on. I'm half scared to drive mine.
yeah it its scary at 110mph
Posted By: cudadan
Re: vibration update on the cuda - 11/28/08 03:41 AM
Quote:
i think it's the output shaft. any chance you had two bent ones? when you changed the driveshaft did you use the same front yoke or did you use a different one?
anything is possible, with all of the driveshafts i've tried they all had there own yoke on them, with the same results
Posted By: MIKES_DUSTER
Re: vibration update on the cuda - 11/28/08 03:53 AM
i havent read this whole thread,did you find your problem??
Posted By: cudadan
Re: vibration update on the cuda - 11/28/08 02:07 PM
wish i did Mike, im getting ready to leave to pick up another trans to try that, keep your fingers crossed LOL
Posted By: MoparDonny
Re: vibration update on the cuda - 11/29/08 02:11 AM
You got that trans in yet, Dan? Ha ha!! JK!!
I hope you figure this out tonight! Good luck. You must be pulling your hair out by now.
Don.
Posted By: cudadan
Re: vibration update on the cuda - 11/29/08 03:53 AM
Quote:
You got that trans in yet, Dan? Ha ha!! JK!!
I hope you figure this out tonight! Good luck. You must be pulling your hair out by now.
Don.
i got it lol, just pulled the trans out of the car, and tomorrow morning the new one goes back in. please please please don't vibrate LOL i'll have an update probably by lunch time
Posted By: superwrench
Re: vibration update on the cuda - 11/29/08 06:49 AM
Well...if it doesn't fix it, HemiFred seems like he's game for attending a Car-B-Cue!!
Good luck Dan....I can't imagine the frustration.
Posted By: fullmetaljacket
Re: vibration update on the cuda - 11/29/08 06:50 AM
Cudadan.
If you have an front engine plate holding your motor in place, you might want to make sure the motor is aligned with the propeller shaft and rear in the right orientation. I think I might have the same issues also with this.
Make sure your front end is tight and aligned.
Make sure your rear springs have no broken leafs.
Check the rear spring center bolt that centers the leafs onto the rear housing
Check the front rear spring hangers and the front rear spring eye bushing for wear.
Posted By: cudadan
Re: vibration update on the cuda - 11/29/08 03:41 PM
well the trans is out, and i pulled the flexplate to get a better look at it and saw that 2 of the torque converter hole were a lil worn, and the other 2 are perfect, would the 2 hole that are perfect keep it all inline? not sure if this is the problem,
just went out and bolted the flexplate to the converter kept the bolts loose and i cant turn the flexplate on the converter it fits nice and tight no moverment
http://picasaweb.google.com/cudadan360/Flexplate?authkey=WKEd3o52m3Y#
Posted By: MoparDonny
Re: vibration update on the cuda - 11/29/08 08:24 PM
Can't see that little bit of wear causing you any problems. Patiently awaiting some good news!!
Don.
Posted By: cudadan
Re: vibration update on the cuda - 11/29/08 08:29 PM
well no good news just yet
this other tranny slips, cant tell if im in 2nd or 3rd, but at 1800 rpms @35mph this trans doesnt vibrate at all, still dont know if its slipping so bad that i can set it where i want, so im gonna pull my manual vavle body and put it in the other trans so i know that i am in 3rd gear, i can't win i tell ya
Posted By: SomeCarGuy
Re: vibration update on the cuda - 11/29/08 08:51 PM
Unfing believeable
Posted By: cudadan
Re: vibration update on the cuda - 11/29/08 09:01 PM
Quote:
Unfing believeable
could'nt have said it better myself, gonna swap the valve bodys now so i know im in 3rd with the manual valve body
Posted By: cudadan
Re: vibration update on the cuda - 11/29/08 10:37 PM
well i put my manual valve body in the trans and now it goes through all the gears nice, BUUUUUUUUT i still have a vibration, lets see 3 trannys, 6 drive shaft's, billet yoke, 3 center sections, 3 set of axles, pinion angle has been changed 10x's. 2 sets of tires and wheels, and another set of brake drums, probably 20 u joints., bushings are all in great shape, no cracks in the frame, new tranny mount, motor mounts. this is vibrating without the axles in the rear, sooooo what do i @^&^%$#& do now?
Posted By: smokinwoody
Re: vibration update on the cuda - 11/29/08 10:48 PM
gotta be in the engine somewhere...you've done everything else but change the axle housing...could that have a slight bend?
Posted By: cudadan
Re: vibration update on the cuda - 11/29/08 11:08 PM
Quote:
gotta be in the engine somewhere...you've done everything else but change the axle housing...could that have a slight bend?
it could have a bend but i wasnt sure with running it without the axles that it would vibrate, i am at a total loss here
Posted By: superwrench
Re: vibration update on the cuda - 11/29/08 11:15 PM
He ran it with no axles so I doubt it could be the housing. This is frustrating for me too. Ha ha!! Can't even think of what to try next but it must be up front. What converter is in it now? the stock one or your good one? What about running it with the converter unbolted, are you absolutely sure there is no engine vibration. I thought the B&M plate with the section missing was for a 360 with weight on the converter but You had a balanced converter did you not?
Posted By: topfueldart
Re: vibration update on the cuda - 11/30/08 09:50 AM
Quote:
What converter is in it now? the stock one or your good one? What about running it with the converter unbolted, are you absolutely sure there is no engine vibration. I thought the B&M plate with the section missing was for a 360 with weight on the converter but You had a balanced converter did you not?
There is no way to start the car if the flexplate is unhooked... the starter spins the converter, not the flexplate, unfortunately we arent chevy boys in this aspect...
On page 3 you said you tested the car with the driveline removed and it was smooth as glass, and that it had to be behind that, so why did you rip the trans out of the car to try this other one?
Also, you asked about the measurement side to side of the driveline in the car, and the motor, trans, and drivelines in our cars are all offset about 1 3/4 inch, for the steering column and gear, thats how they came factory, so I dont think thats an issue...
Heres how I diagnose it...
If its REALLY only in 3rd gear, and it changed RPM/speed with all 3 chunk swaps, then its a drivetrain RPM issue, and not an engine RPM issue, so it CANNOT be motor, flexplate, converter, front pump, or input shaft related... its gotta be in the back of the trans rearward...
If it REALLY went away without the driveline in the car, that proves all of that as well, unfortunately it doesnt really rule out the back of the trans, because if the output bushing were worn, then maybe the weight and force of the driveline is straining the trans causing the issue, but since youve had several trannys in the car, i dont think thats the issue..
You probably didnt get MULTIPLE bad drivelines, and u-joints, and you have tested the car without the wheels and brakes, and tried different gear sets with no difference either, so your really running out of possible options here..
SOOOOO pretty much the only thing left is:
Rear end could be installed crooked or bent, maybe the spring mounts, or the whole housing is tweaked or something, causing the u joint to bind, and causing the vibration. your car leave pretty hard, so its probably taken a beating, maybe you should backbrace the next one. Are the U-bolts tight? Those are the only things I think would follow the logic of everything you have said, and explain the issue.
Dont know what else to say man, there is alot of conflicting issues in the thread, and it gets hard to comprehend it all... I think your on the right track trying the rear end next, but if that doesnt fix it, i say just beat on it until something breaks, these old mopars are weird sometimes, it could go on for years lol
Good luck.
Posted By: Anonymous
Post deleted by Defbob - 11/30/08 12:53 PM
Posted By: RemCharger
Re: vibration update on the cuda *DELETED* - 11/30/08 06:40 PM
Post deleted by RemCharger
Posted By: MoparDonny
Re: vibration update on the cuda - 11/30/08 07:35 PM
Dan, If you've had it with trying to figure this out, I'll Gladly give you a flat of Kokanee for the car.
Whatcha think?
Posted By: cudadan
Re: vibration update on the cuda - 11/30/08 09:50 PM
Quote:
Dan, If you've had it with trying to figure this out, I'll Gladly give you a flat of Kokanee for the car.
Whatcha think?
I'LL TAKE IT LOL
Posted By: cudadan
Re: vibration update on the cuda - 11/30/08 09:53 PM
Quote:
Quote:
What converter is in it now? the stock one or your good one? What about running it with the converter unbolted, are you absolutely sure there is no engine vibration. I thought the B&M plate with the section missing was for a 360 with weight on the converter but You had a balanced converter did you not?
There is no way to start the car if the flexplate is unhooked... the starter spins the converter, not the flexplate, unfortunately we arent chevy boys in this aspect...
On page 3 you said you tested the car with the driveline removed and it was smooth as glass, and that it had to be behind that, so why did you rip the trans out of the car to try this other one?
Also, you asked about the measurement side to side of the driveline in the car, and the motor, trans, and drivelines in our cars are all offset about 1 3/4 inch, for the steering column and gear, thats how they came factory, so I dont think thats an issue...
Heres how I diagnose it...
If its REALLY only in 3rd gear, and it changed RPM/speed with all 3 chunk swaps, then its a drivetrain RPM issue, and not an engine RPM issue, so it CANNOT be motor, flexplate, converter, front pump, or input shaft related... its gotta be in the back of the trans rearward...
If it REALLY went away without the driveline in the car, that proves all of that as well, unfortunately it doesnt really rule out the back of the trans, because if the output bushing were worn, then maybe the weight and force of the driveline is straining the trans causing the issue, but since youve had several trannys in the car, i dont think thats the issue..
You probably didnt get MULTIPLE bad drivelines, and u-joints, and you have tested the car without the wheels and brakes, and tried different gear sets with no difference either, so your really running out of possible options here..
SOOOOO pretty much the only thing left is:
Rear end could be installed crooked or bent, maybe the spring mounts, or the whole housing is tweaked or something, causing the u joint to bind, and causing the vibration. your car leave pretty hard, so its probably taken a beating, maybe you should backbrace the next one. Are the U-bolts tight? Those are the only things I think would follow the logic of everything you have said, and explain the issue.
Dont know what else to say man, there is alot of conflicting issues in the thread, and it gets hard to comprehend it all... I think your on the right track trying the rear end next, but if that doesnt fix it, i say just beat on it until something breaks, these old mopars are weird sometimes, it could go on for years lol
Good luck.
my 360 is externally balanced so i need the flexplate with the half moon cut out of it. i hope i can finish up my other rear this week so i can eliminate that, then its gonna be leaf springs i guess. after the the only thing that wasn't changed would be the motor, which i dont think thats the problem but ya never know with a vibration. i would drive it till something breaks but the ujoints fail before anything else will lol
Posted By: joshking440
Re: vibration update on the cuda - 12/01/08 11:38 PM
Is it the Damper????
Could you get an externally balanced flywheel from an old truck???
Posted By: cudadan
Re: vibration update on the cuda - 12/02/08 12:15 AM
Quote:
Is it the Damper????
Could you get an externally balanced flywheel from an old truck???
i had the stock one on for about 5 yrs, then i bought an SFI one with no change either
Posted By: joshking440
Re: vibration update on the cuda - 12/02/08 01:27 AM
The damper??? Could it be the problem, bad damper?
Posted By: RemCharger
Re: vibration update on the cuda - 12/02/08 01:28 AM
I've hurt my brain a fair bit on this too. I would start with the fact that it eats rear u joints. could a guy put a pipe in the rear yoke and see how parallel it is with the car? I would think that would solve that question. next do you have an adjustable pin snubber? try preloading it and driving see if it changes. I think its in the shaft to rear end angle.
Posted By: cudadan
Re: vibration update on the cuda - 12/02/08 01:45 AM
Quote:
I've hurt my brain a fair bit on this too. I would start with the fact that it eats rear u joints. could a guy put a pipe in the rear yoke and see how parallel it is with the car? I would think that would solve that question. next do you have an adjustable pin snubber? try preloading it and driving see if it changes. I think its in the shaft to rear end angle.
i just finished up sandblasting my other rear housing, then its off to powder coating, tomorrow i had to move the pearches in .800 for the offset shackel. and should have it ready to go my car monday., i do have an adj pinion snubber, but do you think that on jackstands with NO axles in the car that there would be any strain or stress anywhere., its at 1800 rpms @35mph is where i feel it. then it goes away between 45 to about 75 then it comes back. i checked the wheel base and its only 1/8" different from driver to passenger side..
Posted By: WilliamHall
Re: vibration update on the cuda - 12/02/08 08:34 PM
Is it the same torque convertor you had before and after the vibration problem happened?
Posted By: cudadan
Re: vibration update on the cuda - 12/02/08 09:59 PM
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Is it the same torque convertor you had before and after the vibration problem happened?
yes it is, but i had it sent out to get freshened up , then it got rebalanced
Posted By: MoparDonny
Re: vibration update on the cuda - 12/03/08 03:00 AM
So Dan
Where ya gonna start lookin from here? Almost time to hire a Vibration Analyst.
Don.
Posted By: cudadan
Re: vibration update on the cuda - 12/04/08 01:03 AM
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So Dan Where ya gonna start lookin from here? Almost time to hire a Vibration Analyst.
Don.
lmao, not sure yet maybe a for sale sign hahah. i just finished up my new rear,( 8 3/4) had to move the pearches in. now its ready for powder coating, i should get it back monday or tuesday, then i drop that in and see
Posted By: Anonymous
Post deleted by Defbob - 12/04/08 01:36 AM
Posted By: mopar_mark
Re: vibration update on the cuda - 12/04/08 07:54 AM
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Almost time to hire a Vibration Analyst.
Dan, I can get one of those from my new 8.50 index car's sponsor "CHEERLEADERS". Many girls there have a PHD in that field
Batteries not included 
Posted By: Anonymous
Re: vibration update on the cuda - 12/04/08 12:42 PM
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Almost time to hire a Vibration Analyst.
Dan, I can get one of those from my new 8.50 index car's sponsor "CHEERLEADERS". Many girls there have a PHD in that field
Batteries not included
i got the hookup on the batteries. Tell me where to bring them and I'll hand them off personally
Posted By: cudadan
Re: vibration update on the cuda - 12/04/08 12:46 PM
ROFLMAO, now this is getting good
Posted By: ThermoQuad
Re: vibration update on the cuda - 12/04/08 02:37 PM
I feel your pain and I have read the thread several times now.
It eats rear u joints-it should not eat u joints-that maybe the end result of what the real problem is.
Have you re-torqued the u bolts?
Have you inspected the springs for a bad bushing, cracked leaf etc.
Did you put the car on jack stands under the lca's and rear axle at ride attitude & plot the ctr pt of each wheel on the floor using a plumb-bob to see how "square" your wheels are? Uh-oh I am giving away secrets now...
It eats u joints is the clue..
Posted By: RemCharger
Re: vibration update on the cuda - 12/04/08 04:03 PM
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Almost time to hire a Vibration Analyst.
Dan, I can get one of those from my new 8.50 index car's sponsor "CHEERLEADERS". Many girls there have a PHD in that field
Personal Handheld Device?
Posted By: Anonymous
Post deleted by Defbob - 12/04/08 06:11 PM
Posted By: rowin4
Re: vibration update on the cuda - 12/04/08 07:26 PM
Fred, don't you have to pass the test [find the problem and fix it} before you get the certificate?
Posted By: cudadan
Re: vibration update on the cuda - 12/05/08 12:49 AM
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ROFLMAO, now this is getting good
omg Fred you are killing me, well i am thinking that its the motor i clamped a pc of Aluminum all over the underneath of the car and at the rear it barely moved when i got closer to the motor it was springing like a diving board from the tranny forward
Posted By: David_in_St_Croi
Re: vibration update on the cuda - 12/05/08 01:05 AM
Have you checked the condition of the harmonic damper?
Posted By: cudadan
Re: vibration update on the cuda - 12/05/08 02:50 AM
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Have you checked the condition of the harmonic damper?
brand new and does the same as the old one lol, i am gonna try a new flex plate just for the hell of it
Posted By: RemCharger
Re: vibration update on the cuda - 12/05/08 03:13 AM
If it was in the motor /front trans area, wouldn't it vibrate with engine rpm and/or in nuetral?
Posted By: cudadan
Re: vibration update on the cuda - 12/05/08 06:01 PM
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If it was in the motor /front trans area, wouldn't it vibrate with engine rpm and/or in nuetral?
it do feel some vibes but not as bad, but when you sit in the car in 3rd gear 35mph @1800 it feels like your teeth are gonna fall out of your head, when you go under the car and feel the rear housing, you can barely feel it, go to the trans mount area shaking like shakes more than an 1/8. it is so bad.
Posted By: sleepyhead416
Re: vibration update on the cuda - 12/05/08 07:58 PM
What type of motor mounts do u have?
Posted By: Defbob
Re: vibration update on the cuda - 12/05/08 10:34 PM
rims bent?
Posted By: RemCharger
Re: vibration update on the cuda - 12/06/08 12:05 AM
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If it was in the motor /front trans area, wouldn't it vibrate with engine rpm and/or in nuetral?
it do feel some vibes but not as bad, but when you sit in the car in 3rd gear 35mph @1800 it feels like your teeth are gonna fall out of your head, when you go under the car and feel the rear housing, you can barely feel it, go to the trans mount area shaking like shakes more than an 1/8. it is so bad.
I had a cast crank 440 with steel balancing stuff on it. I've got a 383 with a shimmy stemming from the convertor hub being out of whack. Both of those deals you could feel vibrations at 35 mph. BUT, you could, (and I did 
) race them. They were fine as far danger goes, just not too good on the bearings. Both of them had the exact same vibes in nuetral as driving. Your deal has got to be at driveshaft speed . If you go under the car, how hard is it the physically move the pinion snout around?, pretty hard. Now try moving the rear of the tranny around, somewhat easier. If there is a d/s issue even at the rear, its going to start tossing the tranny around. Its hard to diagnose from 8 million miles away, but when you keep saying its scary at 80 miles an hour, I find it hard to believe its engine rpm related. You would know it in neutral... 
Posted By: SomeCarGuy
Re: vibration update on the cuda - 12/06/08 01:46 AM
Since you swapped out every other thing, I would think a motor swap would not be much more work at this point.
Posted By: cudadan
Re: vibration update on the cuda - 12/06/08 05:53 PM
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Since you swapped out every other thing, I would think a motor swap would not be much more work at this point.
thats what im gonna do, im putting in a bad a$$ lil 340 to check, probably right after the holidays. 340 is for sale too.
Posted By: sleepyhead416
Re: vibration update on the cuda - 12/15/08 08:51 PM
Any UPDATE dan ??
Posted By: sixpackgut
Re: vibration update on the cuda - 12/15/08 09:14 PM
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Since you swapped out every other thing, I would think a motor swap would not be much more work at this point.
thats what im gonna do, im putting in a bad a$$ lil 340 to check, probably right after the holidays. 340 is for sale too.
your going to sell a 340 ci vibrator?
do you have a pulley on the balancer?
Posted By: 65_gt_rag_402
Re: vibration update on the cuda - 12/15/08 09:37 PM
sounds like you have a cracked flex plate or the wrong one . Strokers are balanced different than a non stroker engine .
maybe converter issues ?
Posted By: cudadan
Re: vibration update on the cuda - 12/21/08 05:14 PM
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Any UPDATE dan ??
not yet the motor will be out just after xmas, and the 340 goes in. hopefully by the end of next week i'll have an update
Posted By: cudadan
Re: vibration update on the cuda - 12/21/08 05:16 PM
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Since you swapped out every other thing, I would think a motor swap would not be much more work at this point.
thats what im gonna do, im putting in a bad a$$ lil 340 to check, probably right after the holidays. 340 is for sale too.
your going to sell a 340 ci vibrator?
do you have a pulley on the balancer?
the 340 doesnt vibrate its the 360 that does,,
and i know its not the wrong flexplate cause its been in the car for 5 yrs
Posted By: PC-CHARGER
Re: vibration update on the cuda - 12/21/08 05:46 PM
I can't recall which flex plate you had and I don't feel like reading 6 pages to find out if it was a weighted unit but I assume you do know that generally a 340 is internal balance and 360's are external balance? As such, they require specific harmonic balancers and converters/flex plates. If you install a converter that is neutral balanced on a 360 that requires an externaly balanced converter and damper, it will shake like he!! Same thing the other way.
Posted By: cudadan
Re: vibration update on the cuda - 12/21/08 06:16 PM
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I can't recall which flex plate you had and I don't feel like reading 6 pages to find out if it was a weighted unit but I assume you do know that generally a 340 is internal balance and 360's are external balance? As such, they require specific harmonic balancers and converters/flex plates. If you install a converter that is neutral balanced on a 360 that requires an externaly balanced converter and damper, it will shake like he!! Same thing the other way.
i do have all the correct stuff for the 360, as for ther 340 im using everything from that motor,,,
LOL fred 
Posted By: cudadan
Re: vibration update on the cuda - 01/06/09 02:31 AM
well i got the 340 in the cuda and the vibes arrrrrrrrrrrrrrrrrrrrrrrre alllll gone. so somehwere in the motor something is letting go, gone pull the bottom end apart sometime this week to see whats going on
finally i can sleep at night lol, thx for all the help guys
Posted By: sixpackgut
Re: vibration update on the cuda - 01/06/09 04:06 AM
Posted By: aarcuda
Re: vibration update on the cuda - 01/06/09 04:13 AM
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well i got the 340 in the cuda and the vibes arrrrrrrrrrrrrrrrrrrrrrrre alllll gone. so somehwere in the motor something is letting go, gone pull the bottom end apart sometime this week to see whats going on
finally i can sleep at night lol, thx for all the help guys
wait a minute. you mean you dont know what it was yet? why you little 
Posted By: Triple Threat
Re: vibration update on the cuda - 01/06/09 04:16 AM
Wow, Glad to see you got the issue resolved. Only could wish it would have been easier. Now my car, it still vibrates, let me know when you wanna help track that one down.
Posted By: superwrench
Re: vibration update on the cuda - 01/06/09 04:40 AM
This is getting interesting.
I'd sure like to know what could cause a vibration like that "internally"....woulda been the last place I'd have looked.
Whad'ya think?......what could "Loose" or "Gain" weight to unbalance the engine?
It's gotta be something stupid like a blown intake gasket/head gasket.
Posted By: Anonymous
Post deleted by Defbob - 01/06/09 08:08 AM
Posted By: cudadan
Re: vibration update on the cuda - 01/07/09 12:48 AM
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good lord it only took 6 months
hell i think it was longer than that, hey Fred ya got a spare HEMI laying around lol
Posted By: cudadan
Re: vibration update on the cuda - 01/10/09 08:03 PM
well i go to pull the cam out and it doesnt wanna move, i can barely spin it at all, it took some elbow grease to get it out A LOT OF IT, the middle cam bearing is toast , but the cam itself seems fine, it's not going back in, oil was all clean also cut the filter apart and was all clean
Posted By: RyanJ
Re: vibration update on the cuda - 01/10/09 08:15 PM
That's all you found a spun cam bearing????
Does this motor have a gear drive on it?
Posted By: cudadan
Re: vibration update on the cuda - 01/11/09 04:27 PM
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That's all you found a spun cam bearing????
Does this motor have a gear drive on it?
,, visually thats all i saw wrong, just the cam bearing, the center one walked and covered the oil hole, no gear drive. gonna have the crank spun and the rods checked this week,, i have another 360 i just picked up friday im gonna use.