Re: Driveshaft danger?
[Re: Kern Dog]
#2259228
02/25/17 01:13 PM
02/25/17 01:13 PM
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Posts: 992 Simi Valley, CA
MoparJ
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It sucks when you think you have a problem pinpointed and spend money only to see that the symptoms continue. ALL car guys deal with this! Oh I am quite alright with it. It needed a bigger unit for down the road and this one has more engagement into the transmission. It was a good investment.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
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Re: Driveshaft danger?
[Re: Sxrxrnr]
#2259234
02/25/17 01:27 PM
02/25/17 01:27 PM
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MoparJ
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I have a friend whose Mopar mechanical and automotive skills I have great respect for, insists that a driveshaft yoke shoved into a transmission bushing with too much clearance is the root cause of many unexplained intransigenet driveline vibration issues.
He recommends a new bushing which is too tight and honing it out to fit the specific yoke you are using. He suggests with the transmission out of gear to relieve stress on driveline, to attempt to move the yoke up and down. Any permitted movement is indication of potential problem.
I will forward this thread to him for comment. Sounds good. Yes, although there really wasn't any play at all on the slip yoke, I am starting to think the tailshaft bushing is the culprit. Realistically, the transmission as a whole is kind of tired. It leaks a bit from somewhere on the left side after sitting overnight and has for a while. I add fluid when needed every 2 or 3 months. First gear (not in it long because it is so short) whines some. All and all, I think it needs a freshen. Until I can, I'll just ride around and not be too harsh on it. Since the mentioned minor pulsating vibration is more evident in 4th/OD, I will just keep from using it as much as possible except on the highway (just in case it is something in that gear as well) I usually do that anyways.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
Searching for new A or B Body Project!
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Re: Driveshaft danger?
[Re: MoparJ]
#2259637
02/26/17 02:30 AM
02/26/17 02:30 AM
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Joined: Nov 2003
Posts: 36,041 Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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Just me I would borrow another 8&1/4 rear to confirm or elim that. in my head I keep coming back to that. Do post the outcome (no matter how long it takes).
live every 24 hour block of time like it's your last day on earth
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Re: Driveshaft danger?
[Re: Sxrxrnr]
#2259655
02/26/17 05:48 AM
02/26/17 05:48 AM
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Joined: Jul 2013
Posts: 1,272 Northern Calyfornua
Sxrxrnr
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I have a friend whose Mopar mechanical and automotive skills I have great respect for, insists that a driveshaft yoke shoved into a transmission bushing with too much clearance is the root cause of many unexplained intransigenet driveline vibration issues.
He recommends a new bushing which is too tight and honing it out to fit the specific yoke you are using. He suggests with the transmission out of gear to relieve stress on driveline, to attempt to move the yoke up and down. Any permitted movement is indication of potential problem.
I will forward this thread to him for comment. As my friend is not a member of this forum but he did send this response to me after I had forwarded a copy of this thread to him. The following is a "copy and paste" of his response. Roger: It looks like you explained it well but I'm happy to provide you something you can cut and paste as I am not a member there. However some members on this site may carry over to the FBBO forum and would recognize me by my handle Meep-Meep. The sign of slip yoke vibration is to drive the car close to or at freeway speed and find that spot where you "float it" by not being under power or deceleration. Just modulate the throttle until you hear that grumble sound and you will find you are not loading the drive line, thereby allowing the yoke to rattle around in the tail housing. This is independent from a balance issue since an out of balance shaft will try to orbit around it's center of mass even with a properly fitted bushing. It's been my experience lately with slip yokes that the clearance is way too loose even when replacing the parts with new. And by way too loose I mean over about .007" is too loose. For a quick test on an unloaded drive line (tranny in neutral and rear wheels off the ground) grab the front yoke and attempt to move it up and down and you should have little to no perceptible motion. I don't have the actual dimensions off the top of my head but for sure the new yokes that I measured are small and the bushings are perhaps bigger than they should be. My yoke reference is taking the measurement on the non worn part on a factory yoke. One car I had measured over .060" and others are in the .020" range if memory serves and all have the grumble to some varying degree. Granted taking a dial indicator measurement way out at the U joint will show a pretty big number but it's still a reference. The fix is to fit the bushing to the yoke with the proper clearance, and since the yoke is the part more likely to be replaced or changed, it would make sense to make an undersized custom bushing and hone it to fit the new yoke. For honing I will take my next tail shaft and yoke to a machine shop that has the Sunnen hone like the kind used to resize rods and tell them it's like fitting a piston pin (but not piston pin clearance). This will ensure a non tapered round bore. The only catch is the bushing bore needs to be in proper alignment with the output shaft bearing all the way up to the pilot bearing or front pump bushing. Alex Lobodovsky
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Re: Driveshaft danger?
[Re: Sxrxrnr]
#2260410
02/27/17 12:40 PM
02/27/17 12:40 PM
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Joined: Feb 2008
Posts: 992 Simi Valley, CA
MoparJ
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I have a friend whose Mopar mechanical and automotive skills I have great respect for, insists that a driveshaft yoke shoved into a transmission bushing with too much clearance is the root cause of many unexplained intransigenet driveline vibration issues.
He recommends a new bushing which is too tight and honing it out to fit the specific yoke you are using. He suggests with the transmission out of gear to relieve stress on driveline, to attempt to move the yoke up and down. Any permitted movement is indication of potential problem.
I will forward this thread to him for comment. As my friend is not a member of this forum but he did send this response to me after I had forwarded a copy of this thread to him. The following is a "copy and paste" of his response. Roger: It looks like you explained it well but I'm happy to provide you something you can cut and paste as I am not a member there. However some members on this site may carry over to the FBBO forum and would recognize me by my handle Meep-Meep. The sign of slip yoke vibration is to drive the car close to or at freeway speed and find that spot where you "float it" by not being under power or deceleration. Just modulate the throttle until you hear that grumble sound and you will find you are not loading the drive line, thereby allowing the yoke to rattle around in the tail housing. This is independent from a balance issue since an out of balance shaft will try to orbit around it's center of mass even with a properly fitted bushing. It's been my experience lately with slip yokes that the clearance is way too loose even when replacing the parts with new. And by way too loose I mean over about .007" is too loose. For a quick test on an unloaded drive line (tranny in neutral and rear wheels off the ground) grab the front yoke and attempt to move it up and down and you should have little to no perceptible motion. I don't have the actual dimensions off the top of my head but for sure the new yokes that I measured are small and the bushings are perhaps bigger than they should be. My yoke reference is taking the measurement on the non worn part on a factory yoke. One car I had measured over .060" and others are in the .020" range if memory serves and all have the grumble to some varying degree. Granted taking a dial indicator measurement way out at the U joint will show a pretty big number but it's still a reference. The fix is to fit the bushing to the yoke with the proper clearance, and since the yoke is the part more likely to be replaced or changed, it would make sense to make an undersized custom bushing and hone it to fit the new yoke. For honing I will take my next tail shaft and yoke to a machine shop that has the Sunnen hone like the kind used to resize rods and tell them it's like fitting a piston pin (but not piston pin clearance). This will ensure a non tapered round bore. The only catch is the bushing bore needs to be in proper alignment with the output shaft bearing all the way up to the pilot bearing or front pump bushing. Alex Lobodovsky Very good information and thank you. Grumble is a great description and yes it is in the highway float zone, not under acceleration. Considering I have eliminated a few things and will look into the rear today, this is starting to look like the likely culprit. There is still a hair bit of play, probably .030" or less, in the pinion slip yoke, but it is play nontheless. I'll probably deal with it for a while if so, until I can rebuild the transmission as a whole in the summer.
Last edited by MoparJ; 02/27/17 12:49 PM.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
Searching for new A or B Body Project!
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Re: Driveshaft danger?
[Re: None2Slow]
#2260413
02/27/17 12:43 PM
02/27/17 12:43 PM
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Joined: Feb 2008
Posts: 992 Simi Valley, CA
MoparJ
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This months issue of Hot Rod (April 2017) has an article helping a guy with the same problem your having,only his was worse. Hot Rod Rescue is the article. He went through everything, even taking it to a 4x4 shop because he was being told his angles were off. It was a combination of a lot of things, including transmission dowel pins out of alignment. Right now your just speculating and throwing money at a problem hoping to find a cure. Pick it up and read, very enlightening. My dad actually showed me this article yesterday and we were looking it over. Very enlightening. Pinion angle is taken care of and confirmed a non issue as of yesterday. Alignment all looked good. I am ok with the money I had spent so far, since new back tires were needed and a more robust driveshaft was preferred.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
Searching for new A or B Body Project!
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Re: Driveshaft danger?
[Re: dart4forte]
#2264419
03/06/17 05:57 PM
03/06/17 05:57 PM
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Joined: Feb 2008
Posts: 992 Simi Valley, CA
MoparJ
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Drove it a few days to work and back last week, about 130 miles total, mixed driving. Probably will again this week if weather warms up more. Grumbling, minor pulsating vibration is still there. Can feel in throttle and steering wheel, in the area of the transmission or very front of driveshaft. Still mostly perceptible in the throttle float zone when cruising above 55mph. Not really discernable during acceleration. Can feel some of it when I push in the clutch at highway speed. Driveline angles are essentially in line, with the slip yoke off maybe .15-.25° compared to the rear yoke at most. Certainly feeling that it is more likely that the source of what I am feeling from the rear of the transmission, more specifically the tailshaft bushing. There is a bit of side to side play. The transmission is in need of a refreshing soon to begin with, since it is a leaker from the speedometer gear area.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
Searching for new A or B Body Project!
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Re: Driveshaft danger?
[Re: gtsdude]
#2264596
03/06/17 10:56 PM
03/06/17 10:56 PM
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MoparJ
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FWIW my buddy had a vibration like you describe in his 66 fairlane with 4 speed, pulled apart the trans and had 2 bad bearings along with a bad trans mount that made it worse. Yeah, wouldn't surprise me if I have similar with my tired transmission. The trans mount is fairly fresh, but I have an extra poly bushing that I might try.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
Searching for new A or B Body Project!
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Re: Driveshaft danger?
[Re: MoparJ]
#2265636
03/08/17 03:58 PM
03/08/17 03:58 PM
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Joined: Feb 2008
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MoparJ
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Update: drove 40 miles into work today. Grumbling resonance/light vibration is most present between 55-65 mph in 4th and I feel it more through the accelerator pedal, clutch pedal when I press it in and in the shifter handle. Not really under seat or rear ward. Pushing clutch in, it’s still there but much reduced. Same when popping into neutral (greatly reduced). Centering more and more on somewhat worn tailshaft bushing.
As mentioned, roughness while holding revs north of 1800 rpm in neutral is present, but has been for quite a while since the new motor mounts were put in.
Other than that, car ran good on the way into work; all vitals are good, temp and pressure wise.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
Searching for new A or B Body Project!
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Re: Driveshaft danger?
[Re: Sixpak340]
#2332064
07/05/17 06:16 PM
07/05/17 06:16 PM
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Joined: Feb 2008
Posts: 992 Simi Valley, CA
MoparJ
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Just wondering if you got to the bottom of this. I just had my Goodyear polyglas tires road force balanced and got some improvement. The increased rpm may bring out a tire balance issue that you didn't have previously. Let us know what you have found. The sensation/issue is still there. The front slip yoke does have movement, but not a ton and it has not worsened. I have put about 500 additional miles on the car since my last post. No change or increase in severity. What I have noticed is what seems to be a decrease in the grumble, or at least less noticeable, above 65 mph or 2400 rpm in 4th/OD. After that point, the light vibration/grumble seems much less pronounced. Starting to wonder more about the trans mount, too hard of motor mounts, or a bearing in the trans making some commotion at specific RPM in 4th/OD.
2016 Ram 1500 Crew Cab: 5.7, 65RFE, 4.56 gears with locker, Hemifever tuned, AFE intake, 87mm throttle body, JBA headers, 3" Flowmaster exhaust, split to dual 2.5" exits. 13.57 best ET so far.
Searching for new A or B Body Project!
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