B Body Dana 60, Pinion Snubber, Driveline Vibration

Posted By: bulletpruf

B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/24/09 01:43 AM

Fellas -

My 68 RR (hemi, 727, Dana 60) has some driveline vibration at about 60+ mph. Wasn't happening until recently.

Lubed the u joints (I need to swap to solid u joints) today, checked u bolts for tightness. Got pulled over on the test drive (he liked the car, no ticket), but still vibrating.

Car does not have a pinion snubber. When I got underneath, I saw where it looks like the very rear of the driveshaft smacked the floorpan - must have been an extreme angle. My guess is that I tweaked the rear u joint when this happened.

My plan - drop the driveshaft, get solid Spicer u joints installed. Install a pinion snubber. Driveshaft stuff I can handle, but any ideas on a good pinion snubber? Doesn't have to be 100% correct Mopar; car is slightly modified, and it's not going to be concourse judged.

Thanks,

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/24/09 05:21 PM

Driveshaft is out and will go to the shop Monday or Tuesday.

Any recommendations on pinion snubbers?

Thanks,

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 01:28 AM

Feel like I'm having a one-sided conversation here, but I bought a Mopar adjustable pinion snubber from Jeg's...

Posted By: mercman1

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 03:02 AM

Quote:

Feel like I'm having a one-sided conversation here, but I bought a Mopar adjustable pinion snubber from Jeg's...

What rpm is the engine turning when the vibration starts and can you drive through it? Say it starts at 3500 and vibrates til 4800??? will it vibrate in neutral at the same rpm???

Posted By: Magnum

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 04:07 AM

I don't like pinion snubbers. They hinder suspension travel. If the universal joint is going that high from axle wrap it's the fault of weak leaf springs.

Is the vibration speed or rpm related?

I correct my statement. I don't like adjustable pinion snubbers. The factory one will not hinder travel.

Posted By: Jeremiah

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 04:09 AM

The snubber should help the pinion angle stay in a safe area if the rear springs are overcome by the weight transfer of the car. Many say no pinion snubber is needed however I am of the opinion that if you have to have soft springs to get the tires planted a pinion snubber will be very helpful in keeping the pinion angle safe. What springs are in the car now? I would def. have the drive shaft balanced by a known good shop with the new u-joints installed. That said let them put the joints in if you do not have the proper tools or experience. If this is the case as if you can watch. I've seen several shafts ruined by inexperienced, overzealous shadetree mechanics. At the age of 16 I started that list!

If you have trouble getting a response shoot me a PM or

I'd be hapy to share my experiences.

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 04:53 PM

Quote:

Quote:

Feel like I'm having a one-sided conversation here, but I bought a Mopar adjustable pinion snubber from Jeg's...

What rpm is the engine turning when the vibration starts and can you drive through it? Say it starts at 3500 and vibrates til 4800??? will it vibrate in neutral at the same rpm???

I didn't check to see if it was vibrating in neutral. I feel a slight vibration at lower speeds. I also feel some clunking at low speeds when turning.

Does not seem to be rpm related; seems to be more speed related. I did not try to drive through it.

Thanks,

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 04:54 PM

Quote:

I don't like pinion snubbers. They hinder suspension travel. If the universal joint is going that high from axle wrap it's the fault of weak leaf springs.

Is the vibration speed or rpm related?

I correct my statement. I don't like adjustable pinion snubbers. The factory one will not hinder travel.

Leaf springs are brand new, but not sure who manufactured them.

Thanks,

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 04:57 PM

Quote:

The snubber should help the pinion angle stay in a safe area if the rear springs are overcome by the weight transfer of the car. Many say no pinion snubber is needed however I am of the opinion that if you have to have soft springs to get the tires planted a pinion snubber will be very helpful in keeping the pinion angle safe. What springs are in the car now? I would def. have the drive shaft balanced by a known good shop with the new u-joints installed. That said let them put the joints in if you do not have the proper tools or experience. If this is the case as if you can watch. I've seen several shafts ruined by inexperienced, overzealous shadetree mechanics. At the age of 16 I started that list! If you have trouble getting a response shoot me a PM or I'd be hapy to share my experiences.

The driveshaft shop does good work and they're inexpensive, so I'll let them handle this. I need to buy a press before I mangle my own u joints.

I don't like u joints with a zerk fitting anyway, so if this doesn't fix it, at least I've got good u-joints and have hopefully ruled out the driveshaft as the source of the problem.

Thanks,

Scott

Posted By: Jeremiah

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/25/09 11:18 PM

Sounds good. Make sure to check all of the trans bolts, etc. while you are under there. I had a nasty driveshaft vibarto and it shook all kinds of bolts loose and almost wrecked the bellhousing. I also suspect that is ate up the trans mount. Had a new d-shaft cut and all was good other than lots and lots of loose bolts.

I learn the hard way so others don't...

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/26/09 01:14 AM

Quote:

Sounds good. Make sure to check all of the trans bolts, etc. while you are under there. I had a nasty driveshaft vibarto and it shook all kinds of bolts loose and almost wrecked the bellhousing. I also suspect that is ate up the trans mount. Had a new d-shaft cut and all was good other than lots and lots of loose bolts. I learn the hard way so others don't...

Good point. I'll check 'em.

Thanks,

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/27/09 05:43 PM

Driveshaft shop says the front u joint is bad. They'll replace it with a solid joint, straighten, and balance it. Should be back in the car this evening. Maybe I can take a test drive without getting pulled over this time...

Thanks,

Scott

Posted By: 1MYTGTX

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/27/09 05:50 PM

Cool keep us posted....subscribing

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/28/09 10:58 AM

#@)(&$)#@Q*I$~!!!

Driveshaft went back in last night, freshly balanced, straightened, painted, new u joints front and rear. Took her for a drive and the vibration is still there. I only felt it as I was going pretty fast (maybe 60-80 mph?). Goes away when I put it in neutral. Does not appear to be rpm related; don't feel it at high rpms at lower speeds.

This is getting frustrating...

Any other thoughts? I'll check the trans bolts for tightness this weekend.

Thanks,

Scott

Posted By: Snoopy

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/28/09 11:11 AM

What did you determine on the length?
Length should be 50.39" ctr-ctr.

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/28/09 12:56 PM

Quote:

What did you determine on the length?
Length should be 50.39" ctr-ctr.

Good question. The only measurement that I took was after I removed the driveshaft - from the tranny seal to the front of the pinion yoke was 54". Gave that to the driveshaft shop and they said the length was good. I'll measure it center to center this weekend and see what I end up with.

Thanks,

Scott

Posted By: DoctorDiff

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/28/09 01:50 PM

Are you running a poly transmission mount, or a stock (rubber) transmission mount?

What is the angle of your transmission centerline? Up or down toward the rear?

What is the angle of your pinion centerline? Up or down toward the rear?

How much driveshaft travel before the slip yoke bottoms out inside the transmission?

Does the slip yoke fit fairly tight inside the transmsission tail bushing?

Posted By: JohnRR

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/28/09 03:22 PM

Quote:

Driveshaft shop says the front u joint is bad. They'll replace it with a solid joint, straighten, and balance it. Should be back in the car this evening. Maybe I can take a test drive without getting pulled over this time...

Thanks,

Scott

Why would the front joint have gone bad if the rear was what hit the floor?

Also STRAIGHTEN ??? , straighten WHAT ???

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/28/09 08:41 PM

Quote:

Are you running a poly transmission mount, or a stock (rubber) transmission mount?

What is the angle of your transmission centerline? Up or down toward the rear?

What is the angle of your pinion centerline? Up or down toward the rear?

How much driveshaft travel before the slip yoke bottoms out inside the transmission?

Does the slip yoke fit fairly tight inside the transmsission tail bushing?

Only thing that I can answer now is that the slip yoke fits fairly tight inside the tail housing. Will check the trans mount. As for the geometry questions, I'll have to check; I was under it yesterday, but the back end was way up in the air, and I didn't look to see how things were positioned in relation to each other when it was on the ground.

Will report back with details.

Thanks!

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/28/09 08:45 PM

Quote:

Quote:

Driveshaft shop says the front u joint is bad. They'll replace it with a solid joint, straighten, and balance it. Should be back in the car this evening. Maybe I can take a test drive without getting pulled over this time...

Thanks,

Scott

Why would the front joint have gone bad if the rear was what hit the floor?

Also STRAIGHTEN ??? , straighten WHAT ???

Driveshaft shop said that the front joint was old, and it was bad. Probably the result of age, not rear diff rotation. Surprised that they didn't replace the joint when they built the car.

The shaft wasn't bent, but they check for straightness (and straighten it, if it's bent, I guess) when they balance it.

Thanks,

Scott

Posted By: Jeremiah

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/29/09 04:23 AM

Whoa whoa whoa....

If you are rolling along at 80 mph and the vibration is there...and you put the car in N and the vibration goes away...

would you not want to investigate the converter/flexplate/flywheel balance? If the driveline was causing this the vibrato would still be there even in N when the car is rolling. Personally I'd think about finding a different driveshaft shop. It is straight or it's not. If not it needs to be retubed or it will never be correct.

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/29/09 02:17 PM

Quote:

Whoa whoa whoa....

If you are rolling along at 80 mph and the vibration is there...and you put the car in N and the vibration goes away...

would you not want to investigate the converter/flexplate/flywheel balance? If the driveline was causing this the vibrato would still be there even in N when the car is rolling. Personally I'd think about finding a different driveshaft shop. It is straight or it's not. If not it needs to be retubed or it will never be correct.

I do not want to investigate the converter/flexplate balance, but I might end up having to. I want to swap to a 4 speed anyway, so maybe this is the time to do it.

Thanks,

Scott

Posted By: Jeremiah

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/29/09 04:07 PM

Sorry man I did not mean to sound harsh. 'Just thinking out loud to isolate your problem. You'll get it, just takes time and some new gray hair.

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/29/09 08:17 PM

Quote:

Sorry man I did not mean to sound harsh. 'Just thinking out loud to isolate your problem. You'll get it, just takes time and some new gray hair.

I didn't think your response was harsh, and I appreciate the input.

Thanks,

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 05/30/09 08:44 PM

Took it to the local tire shop today. Wheels were all out of balance to some degree. All balanced out, but the two front ones didn't seem to be 100% true (brand new reproductions), so he said that I might still have some slight vibration. Sure enough, the vibration is still there, but significantly reduced. Need to hook up the speedo to see where it kicks in at, but I think it's probably around 70 mph.

Thanks for all the input!

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 06/07/09 05:14 PM

Quote:

What did you determine on the length?
Length should be 50.39" ctr-ctr.

Measured it - it's 50.4" center-center, so I'm good there.

Have the Mopar adjustable pinion snubber installed at the lowest setting. Had to take the grider to it before I could get the pin in.

Thanks again for all the input.

Scott

Posted By: stumpy

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 06/07/09 06:15 PM

Is the vibration in the steering wheel or in the seat of your pants?

Posted By: 68jim

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 06/09/09 01:11 AM

Scott,

Hate to chime in late here but I now find myself in your situation, just a little bit worse... Funny thing is I have the same set up in my car, 68 Road Runner-426-727-4.10 dana and live in Virginia...go figure... Car is a total restoration,and I had my drive shaft balanced prior to installation with new joints. Up to this point I had only driven the car around the neighborhood and a few small burnouts in front of the housewith no issues. I drove the car through town (3 miles/40MPH) for the alignment. After that was done I took it out for the highway run it it felt really good under throttle to about 70 or so and then I let off the throttle and it started the vibrations pretty strong. I slowed down and varied speeds and it seemed like it was more pronounced during deceleration. I took it home and put it up on the lift and everything looked and felt OK. In my mind I was thinking something from the rear end since the vibration was in the body and not the steering wheel. I took it out one more time and still had the same problem...all of a sudden the vibration went away and for a second or so I was pretty happy until I looked out in the mirror and saw nothing but smoke...and I mean a LOT of smoke... The heavy smoke cleared up but I was still getting intermittent puffs as I slowed down and got off the highway. Once off I pulled into a parking lot and discovered trany fluid everwhere under the car. I nursed the car back to the garage but had to go under 25 MPH as the car had vibrations bad enough that I did not want to chance anything by pushing it. Once under the car I found the tail shaft housing in two pieces, it broke just after the mount. Once I got things cleaned up a bit I pulled the driveshaft (the weights are still in place)and the U-joints still feel good through full travel. I spun the shaft out the back of the tranny and it is straight as best as I can visibly see. Good thing was that there was no damage to the body other than the mess from the tranny fluid.
This happened last weekend and I had to leave town before I could have the driveshaft re-checked... I also still need to drop the tranny pan and see if there may be any suprises...I love this hobby...

Anyone else ever bust a tailshaft housing???

Jim
68 Hemi Road Runner

Attached picture 5280664-P2010079.JPG

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 06/11/09 06:58 PM

Quote:

Scott,

Hate to chime in late here but I now find myself in your situation, just a little bit worse... Funny thing is I have the same set up in my car, 68 Road Runner-426-727-4.10 dana and live in Virginia...go figure... Car is a total restoration,and I had my drive shaft balanced prior to installation with new joints. Up to this point I had only driven the car around the neighborhood and a few small burnouts in front of the housewith no issues. I drove the car through town (3 miles/40MPH) for the alignment. After that was done I took it out for the highway run it it felt really good under throttle to about 70 or so and then I let off the throttle and it started the vibrations pretty strong. I slowed down and varied speeds and it seemed like it was more pronounced during deceleration. I took it home and put it up on the lift and everything looked and felt OK. In my mind I was thinking something from the rear end since the vibration was in the body and not the steering wheel. I took it out one more time and still had the same problem...all of a sudden the vibration went away and for a second or so I was pretty happy until I looked out in the mirror and saw nothing but smoke...and I mean a LOT of smoke... The heavy smoke cleared up but I was still getting intermittent puffs as I slowed down and got off the highway. Once off I pulled into a parking lot and discovered trany fluid everwhere under the car. I nursed the car back to the garage but had to go under 25 MPH as the car had vibrations bad enough that I did not want to chance anything by pushing it. Once under the car I found the tail shaft housing in two pieces, it broke just after the mount. Once I got things cleaned up a bit I pulled the driveshaft (the weights are still in place)and the U-joints still feel good through full travel. I spun the shaft out the back of the tranny and it is straight as best as I can visibly see. Good thing was that there was no damage to the body other than the mess from the tranny fluid.
This happened last weekend and I had to leave town before I could have the driveshaft re-checked... I also still need to drop the tranny pan and see if there may be any suprises...I love this hobby...

Anyone else ever bust a tailshaft housing???

Jim
68 Hemi Road Runner

Jim -

Hey, nice car! Do you have any pics you can send? If so, my e mail is bulletpruf_99@hotmail.com

Thanks,

Scott

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 06/11/09 06:59 PM

Quote:

Is the vibration in the steering wheel or in the seat of your pants?

Vibration is in the seat of my pants.

Thanks,

Scott

Posted By: 68jim

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 07/06/09 10:46 PM

Just to close the loop here. I found out that my driveshaft that had been "custom balanced" was not really balanced at all. The new shop check it and it bounced their rig pretty hard. They found that the rear yoke was .015" offset and the front U-joint was undercut allowing it it favor one side. They got it all happy again and I tested it this past weekend and what a difference. It runs up to 90mph and really smooth!!!!! Now if I can figure out why the glove box pops open at speed???

Jim
68 Hemi Road Runner

Attached picture 5337014-DCP02502.JPG

Posted By: bulletpruf

Re: B Body Dana 60, Pinion Snubber, Driveline Vibration - 10/22/09 04:46 PM

Quote:

Quote:

Is the vibration in the steering wheel or in the seat of your pants?

Vibration is in the seat of my pants.

Thanks,

Scott

After driving it again recently, feels like the vibration is coming thru my feet - floorboards. Maybe the exhaust is routed too close to the floorboard. My 70 GTO is occupying my lift (as well as my time and $) right now, but may fiddle with it this weekend.

Thanks,

Scott