AMC 20 rear diff oops.....need options..

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Joe4310
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AMC 20 rear diff oops.....need options..

Post by Joe4310 »

:banghead: Had rear diff in shop for one piece axel install,new bearings, new thrust. Everything looked great. Got it home did install, installed lift, went to do brakes this 4th of July and discovered that brake backing plates are on wrong sides. Meaning ebrake cables want to come into drum from the back not the front as they should. Called the shop and he said get some new bearings and he will make it right. Not my best option. Can't I just pull Axel's and switch sides as AMC 20 is center diff. Any thoughts would be appreciated before I yank this thing back out again.Not a Ful size question but a cj question​, the battery drain on the Cherokee is a whole other search and thread...

BCRAWLER
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Re: AMC 20 rear diff oops.....need options..

Post by BCRAWLER »

You are on the right track, just pull the axles and switch the plates. Should not take any more than a couple of hours. Maybe give your guy a call just to verify that he's not going to void your warranty by you touching it.
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tedlovesjeeps71
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Re: AMC 20 rear diff oops.....need options..

Post by tedlovesjeeps71 »

You'll want to measure the axles when you have them put to verify they are exactly the same length. Some jeeps get tricky and can be offset like 1/2".


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Cecil14
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Re: AMC 20 rear diff oops.....need options..

Post by Cecil14 »

It's a center diff, meaning the pinion is in the middle (at least ish), but the pinion still sits on one side of the ring gear or the other. Odds that the shafts are exactly the same length are slim, but worth a shot. It's easy enough to pull the shafts out and check.


aa
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REDONE
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Re: AMC 20 rear diff oops.....need options..

Post by REDONE »

BCRAWLER wrote:You are on the right track, just pull the axles and switch the plates. Should not take any more than a couple of hours. Maybe give your guy a call just to verify that he's not going to void your warranty by you touching it.
THIS. You can reuse your wheel bearings, especially if they're new. Yank the shafts straight so you can reuse the seals without needing to press the bearings off and back on. You don't need to swap the shafts side-to-side, they can go right back in where they came from. Most time consuming part of the job will be either a) getting your fresh-drums-that-shouldn't-be-stuck-for-absolutely-no-reason-but-are-anyways to pop loose, or b) rebleeding the rear cylinders.
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Joe4310
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Re: AMC 20 rear diff oops.....need options..

Post by Joe4310 »

Appreciate all responses. The thought of once again yanking this thing out, getting it in the truck to the shop back from the shop, back in position,etc.. uhg.. if that's a word. New drums we're never on and new cylinders never filled, just a matter of brake parts and Axel's. Just didn't want to damage and or replace seals and bearings. Gonna tackle Sat. Night if possible...
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REDONE
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Re: AMC 20 rear diff oops.....need options..

Post by REDONE »

Yeah, a slide hammer helps pull the axles straight so you don't mess up a seal, but it's not absolutely necessary. How much of what was used to seal the outside of the seals can determine how hard it is to get them to pop. When you put them back in just use a thin swipe of regular RTV.
79 J-10 (Honcho Mucho) KE0LSU
304/Performance Fuel Injection TBI/MTA1/SP2P/Magnum rockers
T18/D20/D44s&4.10s/33" Mud Claws
Grizzly Locker Rear
4" front spring drop, 5" rear shackle flip
Chevy style HEI (ECM controlled)
Dolphin "Shark" gauges in a fancy homemade oak bezel
3/4 resto, rotting faster than I've been fixing it.
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Stuka
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Re: AMC 20 rear diff oops.....need options..

Post by Stuka »

Wait, why did the shop say YOU have to bring new bearings if they are the ones that screwed it up? They should be fixing that for free.
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Topic author
Joe4310
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Re: AMC 20 rear diff oops.....need options..

Post by Joe4310 »

Agree completely... But when ding dong moment occurs in shop or on jobsite the first thing I do is find a way to get rid of ding dong and deal with it myself. That being said I've had my moments myself. Just looking for that option to take ding dong out of situation.

Topic author
Joe4310
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Re: AMC 20 rear diff oops.....need options..

Post by Joe4310 »

Drivers side 3 inches shorter than passenger and backing plates appear to be pressed on with bearings. G2 one piece. Contacted G2 for replacement bearing kit. Almost had a rolling chassis....

Topic author
Joe4310
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Re: AMC 20 rear diff oops.....need options.. update..

Post by Joe4310 »

Napa re did the bearings, backing plates are on the correct sides, thrust block is out, amazing how much money you can save with patience and doing things yourself. Anybody know if the brake backing plates take a locking washer or not. One side had them one side didn't. Wouldn't that change the torque settings which are minimal to start. Could be over thinking..

rocklaurence
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Re: AMC 20 rear diff oops.....need options..

Post by rocklaurence »

Im late to the topic but the backing plates are symmetrical. You could drill the hole on the other side for the Ebrake cable and then use a rubber plug on the rear un-used hole.
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