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AMC 20 Axle Shimming Update

4K views 3 replies 2 participants last post by  OlllllllOCJ 
#1 ·
>>> Well here's what I found....1985 AMC model 20 wide track 3.31 g.r. Track Loc, 2 piece axles. P.O. welded driver's side nut to hub????? Looks like hub spun, junk yard hub(yellow paint pen marks), original axles. Bought left hub/axle kit. Cut weld, pulled hub, pulled axle...no inner oil seal. Installed: inner oil seal, new bearing, new axle, new race. Now the race was out a good bit, more than original shim. Went to the right side....all kinds of play??????? The AMC axles get shimmed as one unit with the axle forced to the right side(without a shim), through the center of the differential(thrust block) then the left race has to be backed out to the range .004" to .008", thank you again OlllllllOCJ. Then shim the left brake backing plate out with whatever you need. Back to the problem, seems the left inner oil seal wasn't seated enough.?? I guess I didn't use my 2" schedule 40 nipple and cap insertion tool far enough. A couple more whacks. Set race flush with brake backing plate mounting flange...very slight play...you betcha it's in tolerance. Reassembled without shim. And that's the way it is!
 
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#2 ·
In reply to:

....then the left race has to be backed out to the range .004" to .008", thank you again OlllllllOCJ

[/ QUOTE ]

Most welcome.

It's a bunch easyer to just toss in a set of one piece axles huh. If time is money, seems cheaper to me. I won't put back two piece because of what you just described - pita two piece axles.

Looks like you did some serious research.

BTW the one piece kits allow for the thrust block (don't reach it) so each side is setup on it's own.

I put a Detroit in one of mine at the same time as the one piece axle kit... wonder how that would work with the original two piece axles??

Glad that it worked out for you and sorry I wasn't more help.

Dale
 
#3 ·
I found this also: http://www.trailhed.com/axlepage.html

4-** The ability of the Moser axles to be inserted fully may be affected by the "Axle Thrust Block". You may need to remove the spider gears, side gears, and cross shaft out of the rear end and remove the inner "Axle Thrust Block" so the Moser axles will go in all the way. If you have 4.10 gears or lower (numerically higher), you will have to remove the ring gear to get the cross shaft out. Here is a rough drawing of the Model 20 Thrust Block location. When installing one piece axles, I suggest removing the Thrust Block regardless of its affect on the Moser axles.

http://www.trailhed.com/amc20spacer.jpg

** Number 4 may only have to be done on the Traklock equipped rear differential. Consult your manual and/or inspect your differential for a factory installed thrust block .
 
#4 ·
Guess that Superior is the same, here is a bit of what is on the instruction sheet that ships with a Superior Axle Kit.

"This kit will not work with the Powertrax No-Slip Unit in a Trac-Lock, Call Superior Axle & Gear for details."

"8. If the axles bind upon installing the second axle - Call Superior Axle $ Gear at (323) 268-4151. This indicates either a housing dimension problem or differential center block interference."

I also looked at the Detroit Locker Owners Manual and the exploded view shows a thrust block, setup should remain the same.

Dale
 
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