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D30 Pinion Yoke Wobble

D30 Pinion Yoke Wobble
Neuner

Neuner

Old Time Jeeper
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"Oscar":1985 CJ7, 4.0 '98 OBDII, T177, RE 4.5" lift w/ CV Jnts, Dana 300, Dana 30 and AMC 20, 33" BFG KO2s, Raptor Lined Interior and Rustoleum BBQ exterior.
I can wobble my Dana 30 pinion yoke up and down. Haven't had time to check the nut and if it's tight enough. It's not the drive shaft so suspecting a loose nut or bad bearings.

It's my DD so it's only been in 4wd once only to test it out when I purchased it.

Think I'd have to disassemble the whole differential to get to the interior yoke bearing or it might just be the exterior bearing only?
 
Depeding on how loose it is, Take driveshaft off and see if it's the actual pinion gear or just the external connector (yoke?)

If pinion, you said didn't engage front very much, so may be able to just tighten and see, but always safe to remove cover and check stuff out. If nothing else, fresh oil in there... :D

Lumpy will probably be by in a bit - he's good with diff's...

I'm a "take it apart and see" kinda guy...

:chug:
 
Has someone "rebuilt" the axle?? the AMC20 has a crush sleeve that perhaps someone in the past did not have the muscle to crush??
 
On a Dana 30 , there are shims behind the race on the yoke side of the pinion. This is integral to the setting of back lash, and pinion preload. If you can tighten the pinion nut, this may solve some of your problem. If things have worn to an excessive point, it may be time for a rebuild. Merely tightening the pinion nut if things inside are excessively worn inside will do little to solve your problem.
If you can actually "wiggle" the yoke, it sounds like things are extremely worn, but tightening is always worth a try. Worst that happens is it still wiggles.
 
With a wobbling pinion shaft I am amazed that you haven't seen a differential oil leak. Bearing seals don't tolerate any type of side to side motion.

As Mr. Bass said, if your Dana 30 pinion is moving at all at the very least it needs to be properly shimmed up for a proper preload on the bearing. That is seemingly a simple fix is not a simple fix at all. The pinion bearing preload shims are the very deepest adjustment in your differential set up. Essentially you are faced with a complete differential rebuild. Setting the pinion preload can and probably will affect the ring gear depth which affects the backlash, setting the backlash might lead to new bearings, that is if your gears are still in decent condition, wobbling will not be good for the ring and pinion gears .... I.E. nothing in a differential is independent. Do it yourself and you will get an interesting education, pay for it and you will spend ~$1000. If you have been leaning toward adding a locker this would be the time to do it.

Lumpy could do it, since I had his help along with others I could do it, I'm sure many others here can as well, but doing it the first time can be very frustrating. Once you learn the ins and outs the job isn't really bad at all. My experience rebuilding my Dana 30 was a grueling experience. I actually had it right almost on the first try, my notes say the shims I used on the 2nd try were the shims used in the end. Much was learned in the process. Taking what was learned with the Dana 30 to the Dana 44 made the job a relatively easy. Do a trial set up, check the back lash & pattern. Calculate the side shim adjustment and use an educated guess for the pinion shim height adjustment and by god the magic was gone and the logic on how these set ups work paid off. .... unfortunately I don't know how, but I failed to use lock tite and the gear bolts backed out ruining the already questionable axle housing (a bolt punched a hole in the differential housing). But on inspection my jeep guy said it was for the best because the PO thrashed the housing before I got the jeep. With a good used axle housing, along with new bearings and seals the differential was rebuilt again in no time, this time with lock tite in place. .........The point is rebuilding your differential can be a positive experience with lessons that can save a pile of money in the long run.
 
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mriplaybass said:
On a Dana 30 , there are shims behind the race on the yoke side of the pinion. This is integral to the setting of back lash, and pinion preload. If you can tighten the pinion nut, this may solve some of your problem. If things have worn to an excessive point, it may be time for a rebuild. Merely tightening the pinion nut if things inside are excessively worn inside will do little to solve your problem.
If you can actually "wiggle" the yoke, it sounds like things are extremely worn, but tightening is always worth a try. Worst that happens is it still wiggles.
Click to expand...

IO scores a 50% on reading comprehension.
 
IOPort51 said:
IO scores a 50% on reading comprehension.
Click to expand...

I got a good chuckle out of that one. I....wasn't going to to say anything...


Thanks guys, I appreciate it. With what you've said, I think you're correct in a re-build instead of just tightening it. I have a feeling there is damage at least to the bearings. I forgot to consider that the last PO only owned it 6 months while he went through a divorce and beat the $hit out of it. The rear right axle tube of the AMC20 had been bent up and a good cause for me arguing a lower price. It wouldn't surprise me if the Dana 30 play is because of him bashing it around.

Looking at the procedure, I really don't have the proper tools, experience or time for doing this so I think I will take it by a shop. I called 4 Wheel Parts who re-opened their chain here. Quoted me $650 with parts for seals, bearings, etc which sounds about right? I drilled them on the process and they knew all about the crush sleeve, preload, shims etc.

:chug:

Now if I could just find that annoying incessant little rattle that made me discover this, then I would be happy.
 
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Axles expensive, for true and certain.:cool:
 
Older Dana 30 's, use shims, the newer (relatively) use crush sleeves. I don't know how they do it, but some have switched from crush sleeves back to shims. For all the work involved $650 really isn't bad.

Try to be prepared for bad news on the ring and pinion. Gears with tight tolerances don't stand wobbling very well. You can easily spend real money on those, I went with used gears for 1/2 the price. Believe it or not there can be some advantages to using gears that are well worn in. They don't need a break in period, they won't be sending grindings in the oil and you know they are sound with no machining problems.
 
This brings up good memories of Fun times, my AMC20 pinion bearing went out on me in Arkansas, thought it was tranny output that joker howled all the way home


Sent from my iPhone using Tapatalk
 
The 30's in our CJ's use shims and not the dang C'sleeve.
OP-Any updates?
LG
 
Lumpy Grits said:
The 30's in our CJ's use shims and not the dang C'sleeve.
OP-Any updates?
LG
Click to expand...

Nope. Have gotten extremely busy with work. Was hoping to investigate it further over the holiday weekend but so far that looks like it is out.

It will be a while. I'm looking to higher it out but that will be some time from now. I'll remember to come back to this after I get it competed.
 
FWIW: I have seen several D/30 pinion nuts loosen over the yrs. Every one I've seen, didn't have a thread-locker on the threads. The ones I've worked on, IF there was no damage. I would replace the seal and torque the nut to spec. You want 210 ft/lbs of torque on the nut. You MUST use a torque wrench(NO IMPACT)and a few drops of locktite helps here.
LG
 
Finally had some time to look at it closer. With the drive shaft disconnected, I was able to pull the yoke in and out about 1/8 to 3/16 of an inch. It didn't move up, down or sideways which seemed odd. It was smooth when I rotated it and I did not hear any grinding so I'm hoping that's a good sign. I didn't have the proper tools to try and turn the nut. Almost looks rusted in place anyways.
 
You won't be able to move the pinion itself much. It's held in place by the ring gear & bearings.
Get the socket you need to fit and tighten the nut just till all the play is gone. Then go 1/16 of a turn farther.
Center-punch the top of the nut in at least 3 places into the thread of the pinion. Put a strip of paint from the pinion to the nut. If you ever see the paint crack at where the nut and pinion meet. The nut has moved.
LG
 
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Neuner said:
Finally had some time to look at it closer. With the drive shaft disconnected, I was able to pull the yoke in and out about 1/8 to 3/16 of an inch. It didn't move up, down or sideways which seemed odd. It was smooth when I rotated it and I did not hear any grinding so I'm hoping that's a good sign. I didn't have the proper tools to try and turn the nut. Almost looks rusted in place anyways.
Click to expand...



Wow that's not cool, you have a crush sleeve in between the bearings which is supposed to be a one time use only, if tightening the nut doesn't work you will need to replace the crush sleeve


Sent from my iPhone using Tapatalk
 
gert said:
Wow that's not cool, you have a crush sleeve in between the bearings which is supposed to be a one time use only, if tightening the nut doesn't work you will need to replace the crush sleeve


Sent from my iPhone using Tapatalk
Click to expand...
Umm, no crush sleeve in a CJ Dana 30 ... :)
 
I just HATE crush sleeves when do'n R&P set ups.:mad:
I will lathe turn a steel spacer from certified DOM 4140 tubing and use shims for my installs.
LG
 
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