Moparts
727 failure (pics)
Posted By: Anonymous
727 failure (pics) - 04/04/03 02:50 AM
Well, as many may recall I blew the 8 3/4's ring and pinion the last time out last year. Since then, I've purchased and installed a new Dana 60, and 727Jim is in the middle of the trans. rebuild. This was a fresh rebuild on the trans. and everything checked out good, and Todd440 and I used good parts in it when we rebuilt it. The trans. worked pefectly right up until the rear-end failure. This is good reason for tearing down the trans. after a rear end failure.
This is the front planetary. Can you see the stripped splines on the inside?
Bad photo, but this is the strut bar for the front band tension. Its suppossed to be straight!!
This was a brand new bolt in sprag. All the bearings and springs are missing because they were all over the place.
This is the thingy that holds the bearing and springs for the over-running clutch. Ouch!!!
So, I've gathered that after a rear-end failure, the 727 is like a box of chocolates. Youre never sure what youre gonna get. Use a bolt in sprag and a trans. blanket or shield if youre gonna race it. This could have been much worse..
Posted By: 440Jim
Re: 727 failure (pics) - 04/04/03 02:56 AM
Thanks for sharing the pics.
Sorry for the broken parts
Posted By: 69CHARGERMD
Re: 727 failure (pics) - 04/04/03 03:00 AM
"the 727 is like a box of chocolates. Youre never sure what youre gonna get.".......YIKES FORREST !!!
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 03:01 AM
Gary, why did breaking ring and pinion break tranny> Me confused. Glad your getting it done. Heard Jims the man.
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 03:05 AM
Quote:
Gary, why did breaking ring and pinion break tranny> Me confused. Glad your getting it done. Heard Jims the man.
Todd's the man too!! I just had Jim do this one because I'm too busy to get in to it myself like I would have wanted to with Todd, plus I know Todd is busy bustin' tale on the new Coronet. Anyway, I guess its the "shock" of the break in the drivetrain that causes this. sometimes you get lucky, sometimes you dont...
Posted By: gregsdart
Re: 727 failure (pics) - 04/04/03 03:08 AM
Gary, sorry to hear about the breakage! It can be brutal, the front drum sawed its' way right out of a friends barracuda years back, up through the floor, dash, and out the windshield! He was lucky, and only got a hot fluid bath!
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 03:12 AM
Quote:
Gary, sorry to hear about the breakage! It can be brutal, the front drum sawed its' way right out of a friends barracuda years back, up through the floor, dash, and out the windshield! He was lucky, and only got a hot fluid bath!
Greg, I consider myself fortunate. On this particular day I did not have my trans blanket on. I was playing with a new fitting on the trans. earlier in the week prior, and didnt have time to put it back on. It could have been real bad news...
Posted By: earlybee
Re: 727 failure (pics) - 04/04/03 03:16 AM
dayum thats ugly, you might have a looksee at the damper key just for
Posted By: MonGoo$e
Re: 727 failure (pics) - 04/04/03 03:17 AM
wow, very interesting
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 03:19 AM
I am having kelm do me a new Tranny this month. I am finally likking the one in the Dart now. Kelvlar bands eat up the drum or something they said. Anyways, I hope to have it done in a month. I am having Bolt in sprague reguardless of All the guys here who say its a waste.
Posted By: 440Jim
Re: 727 failure (pics) - 04/04/03 03:23 AM
I am going to speculate, since it was asked why.
When the rear end gears break, the trans goes from loaded to unloaded. Then as the rear parts catch a tooth or something, it gets loaded again. This ON-OFF-ON action is what can "disrupt" the rollers/springs in the sprag. This is why manual reverse valve bodies with no rear band apply in 1st need special care when driving in 1st.
Once those rollers start flying around in the trans, something can easily get hung up and the torque of the motor shocking the aluminum splines in the front planetary can strip them right out (output shaft jammed, motor going 6000 rpm suddenly all most stopping except for the torque converter).
Then again, maybe the splines stripped first, causeing weird rotations in the rotating parts that allowed the sprag to come apart.
Posted By: 383man
Re: 727 failure (pics) - 04/04/03 03:26 AM
Damn Mopar power is tuff on them parts.
Sorry to see that Gary. Ron
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 03:34 AM
striped front planets and blown roller clutch failures are pretty common.
4 pinion planets are preferred when building TFs for high performance applications, and most replace three planet pinions when doing the rebuild. there are different splines on the output shafts and one can easily mis match planets and output shafts. I'm building close to 20 years and I've made the mistake we are all human.
as far as the rear roller clutch failure I agree the loading and unloading the transmission in 1st gear will definitly cause the failure. most are under the impression that bolt in sprags will eliminate the failure but in reality it just saves the case.
Just my .02
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 03:41 AM
"loading and un-loading" is what the darn tires did all year.. Lack of traction/good suspension can prove costly...
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 05:08 AM
I hate to look at that stuff because right at the moment, I'm rebuilding mine. I was cleaning my planetaries just a hour ago. I was told putting in one of those bolt in sprags was a waste of money too. I put it in anyway. It's a numbers-matching case and I don't want to risk destroying it if I did something stupid or even accidental, heck, your damage was caused by a failure of another component it seems. Your scenario could happen to anyone. Thanks for sharing the info. I wish I had a couple extra parts to throw your way.
Posted By: JohnRR
Re: 727 failure (pics) - 04/04/03 05:19 AM
Quote:
It's a numbers-matching case and I don't want to risk destroying it if I did something stupid or even accidental
whats the use of this car going to be ? if its out and being rebuilt , and you are concerned with hurting it then NOW is the time to get another case . the bolt in cam for the overrunning clutch (sprague) will only stop the case from stripping , it will not stop a total failure that can and will break the case into multiple pieces .
CDignition showed us a pic last year of his grenaded trans , the front drum came apart and the trans case broke into many pieces ..
Posted By: POZEST
Re: 727 failure (pics) - 04/04/03 05:22 AM
Unlawfl, I know what you mean.....Broken rearend = Nasty 727.......
Good luck!
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 05:30 AM
Hey JohnRR, the bolt in sprag was $33. The Red-Head anchors from which I pulled the sleeves from cost $1.65. It took me 20 minutes to install. If I told you I spent $13 on a brand new output shaft support, you'd probably tell me I wasted my money on that too. Get lost!
Posted By: CrazyRocker70
Re: 727 failure (pics) - 04/04/03 05:30 AM
sorry about your tranny man. i wanted to get my 904 slapstik redone for more of a racing spec. i dont know trannys, but it has to be able to take up to 400 or so hp, and i will drive it on the street alot. but wheni hammer it i want it to launch.. the guy at the treanny shop said he can get my tranny up to that and a new tq converter for 750, am i being ripped off or is this a good deal? what shoul i ask him to do to it to get that kinda performance?
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 06:55 AM
Gary if you need parts give me a list I have a ton of TF8 parts in the shop
Posted By: JohnRR
Re: 727 failure (pics) - 04/04/03 07:16 AM
Quote:
Hey JohnRR, the bolt in sprag was $33. The Red-Head anchors from which I pulled the sleeves from cost $1.65. It took me 20 minutes to install. If I told you I spent $13 on a brand new output shaft support, you'd probably tell me I wasted my money on that too. Get lost!
excuse me ???? at what point did i say that you wasted money ??? i only paid 26 bucks for my bolt in and i made sleeves from a piece of 3 inch tubing , though i paid more for the rear support , so what its not going to stop the trans from blowing to pieces .
my comments were in reply to your concern of hurting your matching number trans . none of the parts your purchased are going to do a thing to stop a front drum explosion or any of the damage that is shown in the pictures above .
whats your matching number matching number trans worth if its broken in 2 ???
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 10:17 AM
We're breaking parts together .... I just replaced my Tailshaft from last weekends expolits. Dvorak put a LARGE (non-standard) pinion nut on the new pinion ... which collided with 1350 joint a some critical pinion angle ... busted a cap ... set up a small vibration (not that I could feel it) and broke the TailShaft housing. My fault for NOT checking everything more closely. Oh how a $5 part can ruin your day! I put a PROPER Pinion Nut and Washer and rechecked it's clearance thrice.
Gary, get a Low Band Apply VB and you'll really minimize chance that you'll bust a sprag ever again. Low Band Apply saves sprags and feet. That boltin sprag is ONLY to save the case. Put that Blanket ON!
Posted By: STEFF
Re: 727 failure (pics) - 04/04/03 01:05 PM
"Oh, the humanity".
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 01:13 PM
Posted by Harpo: "Gary, get a Low Band Apply VB and you'll really minimize chance that you'll bust a sprag ever again. Low Band Apply saves sprags and feet. That boltin sprag is ONLY to save the case. Put that Blanket ON! "
Harpo, I think the new Griner valvebody may have low band apply. It does make me somewhat nervous though. I never thought much of it, but Chuck from Best Machine was telling me that a low band apply valve body can be scary in some situations. Lets say you launch the car and something happens or you get squirrely. When you get out of it, all of the cars weight dives to the front.. We'll see how it goes if the Griner is low band apply..
Posted By: Bubba
Re: 727 failure (pics) - 04/04/03 01:17 PM
Dude Sweet!.......... .I mean that's terrible! Sorry to hear about your lose. You get a Camera? I'm not SLURP good SLURP enough SLURP for you anymore? SLURP.
Posted By: 440lebaron
Re: 727 failure (pics) - 04/04/03 01:54 PM
Hello,
also front band strut bent from line pressure above 120 or so lbs. what i have done is double up with 2 struts welded togeather. i still refuse to run powerglide, just went 8.87 151mph last weekend at US-13 in delaware with torqueflite
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 03:10 PM
Quote:
It does make me somewhat nervous though. I never thought much of it, but Chuck from Best Machine was telling me that a low band apply valve body can be scary in some situations. Lets say you launch the car and something happens or you get squirrely. When you get out of it, all of the cars weight dives to the front..
I guess in the event of a worst case where you break an axle at 6000rpm just prior to 1-2 shift w/ a spool, and the wheels off the ground and jump OFF the throttle it may be a guaranteed handful. When you get out of it under those conditions under good traction, in a No-Band apply VB, it's time to tear the tranny apart. That's why the Non-low Band Apply units have NO 1st gear braking. The braking is the Low/REV band apply.
When I broke my drive shaft last year ... I launch ... it pulls the wheels up .... BANG ... rattle rattle bang bang. I pulled the transmission and checked the Over-running clutch finding no damage, all due to Low Band Apply. IMO It's inherently stronger by design.
Posted By: Anonymous
Re: 727 failure (pics) - 04/04/03 05:30 PM
Posted by Harpo: "I launch ... it pulls the wheels up .... BANG ... rattle rattle bang bang. "
Oh man!! I'm having flash backs!! LOL