My Rear(end) vibrates

Ever since we did the pinion yoke/seal I've had small but noticeable vibration when driving. When we were pulling the drive shaft to pull the yoke we had a small incident... the car lurched off the chocks and rolled about 10 feet down my driveway and dragged the drive shaft down with it. Is it possible this knocked the DS out of balance, I'm also wondering that the U-Joint may have gotten fricked up from that little adventure.

As much as I want nothing to do with your vibrating rear end ( ) I'll throw in my two cents.

Its POSSIBLE the U joint got boogered up, but unless the cap(s) came off and/or you didn't see any noticeable damage when you put it back together I'd say thats less likely.

What would be more likely IMO is the shaft and pinion are now clocked differently than before, relative to each other I mean. I've always read that you should mark the shaft and pinion for alignment before taking it apart, because putting it together in different positions can cause vibrations.

There is also the chance that one of the welded on balance weights on the shaft got ripped off in the ordeal, try checking around your driveway for any slightly curved metal pieces.

There is also the classic "loose nut behind the wheel" problem. Sometimes LOOKING for a problem REALLY hard can make nothing seem like something! Maybe try asking a friend to drive your car a bit, but dont tell him there's a vibration. Let him drive, probe him about it, then ask. If he still thinks it rides smoother than wet butter in a grease factory your brain could be playing tricks on you.

EDIT: Also, didn't think of this before. Been awhile since I've looked at these rear ends, but don't you have to take off the pinion nut to do that seal? In that case did you use a new crush sleeve and torque it back down per factory specs? I dont know how much vibration that would cause if it were the case but that's food for thought as well. Did you check the pinion bearing?

Mr. BBQ wrote:

As much as I want nothing to do with your vibrating rear end ( ) I'll throw in my two cents.

Its POSSIBLE the U joint got boogered up, but unless the cap(s) came off and/or you didn't see any noticeable damage when you put it back together I'd say thats less likely.

What would be more likely IMO is the shaft and pinion are now clocked differently than before, relative to each other I mean. I've always read that you should mark the shaft and pinion for alignment before taking it apart, because putting it together in different positions can cause vibrations.

There is also the chance that one of the welded on balance weights on the shaft got ripped off in the ordeal, try checking around your driveway for any slightly curved metal pieces.

There is also the classic "loose nut behind the wheel" problem. Sometimes LOOKING for a problem REALLY hard can make nothing seem like something! Maybe try asking a friend to drive your car a bit, but dont tell him there's a vibration. Let him drive, probe him about it, then ask. If he still thinks it rides smoother than wet butter in a grease factory your brain could be playing tricks on you.

EDIT: Also, didn't think of this before. Been awhile since I've looked at these rear ends, but don't you have to take off the pinion nut to do that seal? In that case did you use a new crush sleeve and torque it back down per factory specs? I dont know how much vibration that would cause if it were the case but that's food for thought as well. Did you check the pinion bearing?

We marked the drive shaft, but since it was a brand new pinion yoke going on there was no way to "match" the two. Was torqued back to factory. Brand new seal, crush washer and nut. Fluid was also filled to spec with new posi fluid too. Also, one of the caps DID come off the universal, however all the pieces were still there I wanted to spend the $9 on a new U joint but we were both hot and tired and said F it and put the old one back in.

My father drove the car said he didn't notice a vibration, but my brother whose driven my car several times has.

Hmm, fair enough. Unless it was a low quality pinion that was milled at an angle or something, I would say if a balance weight didn't get popped off then I'd try the u joint first. That's easy enough and would certainly eliminate options. If the cap came off then its possible some dirt got in there and is now eating those needle bearings. Maybe you lost a needle or two, I could see that causing a problem. Those damn things are so small.

If nothing else start from square one, is this a problem that you are only now noticing because you're looking for a vibration in the rear end (to make sure the install went ok?) Any chance tires or old bushings/shocks/ etc could be the culprit? And you definitely don't feel it in the steering wheel?

I know I've run circles before trying to find what I put together wrong only to find the problem is somewhere else! You get all wrapped up in what you just did you forget about the rest of the car. As they say, a mind is a terrible thing.

Tom, maybe you havent been lurking long enough to realize...

Whenever Justin fixes something we play this game....

What PART he ef up while trying to fix the original PART.

It's fun....glad your playing along.

Justin, I knew this could be trouble (remember you were going to do it at Mikes Mod Day?)

All I can recommend it to replace the U-joints (both ends...may as well) & hope that solves it.

If not you've compromised the rear end pinion....need someone skilled to reset it.

sdstick wrote:

Tom, maybe you havent been lurking long enough to realize...

Whenever Justin fixes something we play this game....

What PART he ef up while trying to fix the original PART.

It's fun....glad your playing along.

Justin, I knew this could be trouble (remember you were going to do it at Mikes Mod Day?)

All I can recommend it to replace the U-joints (both ends...may as well) & hope that solves it.

If not you've compromised the rear end pinion....need someone skilled to reset it.

Glad I can entertain you Steve.

I knew it couldn't go easy for me. I'll just replace the U joint(s) and go from there. Another forum I was browsing suggested placing the driveshaft in another position on the yoke as it may not be lined up right. So hopefully it's something simple. Oh well, it'll sit til next weekend. I'm leaving for vaca tomorrow.

Cadet57 wrote:

Glad I can entertain you Steve.

Hey...if we cant laugh about this stuff....we'd all be selling our cars as parts..

Does it help if I say your 10X better at this then you were?

Cadet57 wrote:

I knew it couldn't go easy for me. I'll just replace the U joint(s) and go from there. Another forum I was browsing suggested placing the driveshaft in another position on the yoke as it may not be lined up right. So hopefully it's something simple. .......

Well...it COULD go easy but it never seems to for me either.
That yoke change scares me. I efed up a corvette I had once trying this.
I blamed it on the position I was working in & lack of tools...it was still a FAIL

Rotating the shaft is usually a fix for all the SAME parts going back together.
Not that you shouldnt try that EASY step before you go further.
I even remember hearing about pinion yokes being part of the balancing so a different one may be part of the problem.....wish I knew.
Your planning to keep it so new Ujoints are a good 2nd step anyway.
I asked Al to plan on swapping mine so if it gets deeper it can be resolved (or I can blame him )

Yes....I did cringe when you said the car rolled....PLEASE dont do that again.
Enjoy your vacation...

[quote="Cadet57"]

sdstick wrote:

Whenever Justin fixes something we play this game....

What PART he ef up while trying to fix the original PART.

It's fun....glad your playing along.

HAH! I know THAT game all too well! Hopefully this round isn't as maddening as some of the rounds I've had the pleasure of playing.

Sounds to me Justin you should go to Steves house next time you need so work!

I already recommended a better method......

Thanks for helping.....

Dont you have zombie shields or a turret to build or something?

sdstick wrote:

I already recommended a better method......

Thanks for helping.....

Dont you have zombie shields or a turret to build or something?

Lol zombie shields. Lol