Rear Diff rebuild? (1 Viewer)

[hwi1s0n]

Happy, happy to all-

The rear diff in the 60 is leaking so we'll be swapping the pinion seal but folks on the 60 tech board are suggesting there are bigger issues (it makes a grinding sound). Has anyone done this themselves? Should it be left to the pros? If so- whom and how much?


Cheers,


HW

 

[landtank]

That diff is the same as the ones on the 91/92 80s and I have had two with leaky seals that turned out to be a bad pinion bearing.

Ideally the diff should be rebuilt with all new bearings and I would go with a solid spacer. You won't know how the gears are until you open it up.

The cheap way out ios to go to autozone and by an outer wheel bearing for the front of your truck. That should be the same as the outer pinion bearing. Once the flange is moved that pinion bearing should practically fall out as I've had that happen. Then place the new bearing in the hiole and using the pinion nut and washers press it in place. Now you can install a new seal and flange and be on you way. However the durability of this might only be a few miles.

 

[Wildman]

You can try the seal, but usually once you hear the 'growling' in any toy 3rd, the pinion bearings are beyond spent. I have treid it, and it works for a while, (got me back to Umass a few times) but like rick said its only a temporary fix.

Grab a spare 3rd, swap it, and rebuild the one you got. Depending on how bad the bearings are, check to see that the pinion hasn't 'walked' into the carrier.

 

[hwi1s0n]

So are we talking the bearing that's two parts back from the seal or another bearing?

Assuming gears are iffy- what's the cost or difficulty of a complete rebuild?

Thanks again,

Harry

 

[KLF]

The pinion actually rides on 2 bearings, but usually it's the outer one that goes, the one closest to the flange.

Unlike Rick, I've never seen one fall out. I find they typically need to be pressed off the end of the pinion. You might be lucky to get the bearing cage out, but I don't think it's a good idea to replace just the rollers/cage without also replacing the race. They are a matched set. But I guess it would be considered an emergency repair.

Paying for a rebuild should be about $200-250, depending on where you go. Difficulty is relative, it's not something the average wrencher has the tools for.

 

[landtank]

Ken, I was doing a simple seal replacement on Jim Barton's rear 1991. This was the first time I encountered the bearing problem. He was up to my house which is about 2.5 hours from home for him. I pulled the flange and then went in after the seal. When I bumped the pinion it fell into the diff. First thought OMFG! I was able to twist the pinion so it turned itself back out to where I could get the flange back on and set him home.

It actually happened a second time on my son's 91. Both trucks had around 200k on them.

Cost would be dependent on whether or not you pull the third yourself. If you are not comfortable pulling the third then rebuilding the diff is likely out of your ability as well.

 

[KLF]

Oh I totally believe you, I've just never seen it. When I do diff setups, I have a selection of setup bearings for the inner pinion bearing for checking pinion depth, but when I go to pop the pinion back out after removing the carrier, I seem to remember I've always had to whack it with a mallet to get it out of the outer bearing.