AMC 20 Crush Sleeve problem

[billyballer]

I'm finally in the process of regearing the axles in my '86 CJ7. Got the standard Dana 30 front and AMC20 rear. So I set up the AMC20 using setup bearings, after playing around with shim stacks I got a nice pattern and now I'm going for the final install. With the new bearings, races and crush sleeve in place I went to crank down the pinion nut to set the preload and I can't for the life of me get the crush sleeve to crush. I built a custom metal lever that bolts to the yoke to hold it still and then I cranked on the pinion nut, at first I used a breaker bar, then a big breaker par, then a big breaker bar with a pipe on the end, then an even longer pipe. I'm at the point where I'm afraid threads will start stripping or sockets will start shattering.There is still about a 1/4" of in/out play in the pinion so I'm pretty sure it hasn't crushed at all. What do I do? Give the sleeve a little pre-crush? Eliminate the sleeve altogether and just install a solid machined sleeve of the appropriate thickness?

I'm at a loss here.

In better news I just noticed that the picture that appears to the left in everyone's post is pic of my jeep on a trail off of highway 4. Still waiting for my check.
Different pic of the same jeep:

-Bill

 

[Old Dog]

IIRC Ratech sells a solid sleeve for the 20

 

[CJ]

AMC did not use a crush sleeve in the AMC20 diff for CJ's. Preload is set by shim packs. See the image below (no crush sleeve). Where did the sleeve come from? What info did you get that you need one (what manual)?

http://www.jeep4x4center.com/jeep-axle-differential-parts/images/amc-20-rear-cj.jpg

 

[billyballer]

The AMC20 in my '86 has never been opened up and I disassembled it and pulled out a crush sleeve. Maybe they used them in later CJ's?

In that picture you posted item #26 is the crush sleeve. The website indicates this here:
Spacer-Collapsible Pinion 3185971

and here:
AMC Model 20 Rear Axle for Jeep CJ5, Jeep CJ7, & CJ8 Scrambler

The pinion shims in the diagram are used to set pinion depth not preload. Pinion preload would be regulated by the crush washer in this diagram.

Also both Chilton's and Hayne's books that I have indicate a crush washer.
Believe me I wish there was a distance piece with shims...


Thanks for the Ratech tip. That sounds like the way to go.

 

[Old Dog]

heres the link for ya, hope you still have you old crush sleeve to measure
AMC

 

[Purple77CJ7]

I rebuilt my AMC20 a couple of years ago and it had a crush sleeve in it, too. I put in a genuine gear set and rebuild kit with a crush sleeve. I ended up not able to crush the sleeve either. I used it and some big washers and set it to, I think 20 ft/ lbs rotating the whole rear end jacked up. Followed Moses Ludels setup for torque spec. Works good, for 20,000 miles so far.

 

[billyballer]

Just wanted to follow up. I decided to give it one more shot. I extended both the lever I had attached to the pinion flange to about 4.5 feet and the breaker bar to a one piece 6 foot pipe that fit snug over the breaker. Putting all my weight down I was finally able to get the crush sleeve to crush. It went extremely slow and never really seemed to get easier as it crushed, but in the end I got the pinion preload I was looking for. I still think a solid spacer with shims is a better idea.