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AMC 20 rear axle problem...

AMC 20 rear axle problem...

jagj52

Jeeper
Posts
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Location
Morenci, AZ
Vehicle(s)
'86 CJ7 w/4.2L I-6, stock front, rear, & t-case, T-5 manual tranny.
Not to long ago, approx 1 month, the right side of my AMC20 axle broke free while on the trail. The axle shaft is a 1 piece with a fitting that has to be pressed off in order to replace the bearing, race, outer seal, and dust cover. I ordered the replacement parts from Quadratec, took the axle to a local shop to have the fitting pressed off and all of the new parts installed. I got the the axle shaft back an the rear end put back together and within 80 miles the bearing grenaded, and parts were trashed AGAIN!!! Sucks to be me... What I cannot figure is why the bearing would do this. Axle shaft is still straight, no burrs or gouge marks in the shaft, everything bolted back into the housing tightly with very little in and outward play, and no up/down or front/back play. If anyone has had a similar problem and the correct fix please let me know so when I get the FREE replacement parts from Quadratec this does not happen again.:(

Thanks in advance
Allen
 
Bent axle tube perhaps.
 
Were they Timken brand bearings or something that Crown or Omix-ada offered?
 
Were they Timken brand bearings or something that Crown or Omix-ada offered?

^^^that^^^ also did you pack the bearing with grease.
 
you beat me to it, I do not see a trace of grease in that picture
 
I will have to look this through but I thought that the differential oil was supposed to lube the rear wheel bearings.:cool:
 
I will have to look this through but I thought that the differential oil was supposed to lube the rear wheel bearings.:cool:

Not unless you want it to. Typically they are just packed with grease. You can force the diff oil to lube the bearing by leaving the seals out. Im not a big fan of this however.
 
The inner seal prevents the gear oil from getting to the bearing and keeps the grease in. The outer seal keeps the grease in from the other side and also the dirt out. You'd be better off replacing both seals again just in case they got nicked with shrapnel.
 
I stand corrected.:o


I will have to look this through but I thought that the differential oil was supposed to lube the rear wheel bearings.:cool:
 
The axle tube is not bent. I only pulled the shaft to replace the leaking inner and outer seals. The replacement bearing was Crown brand, sold by Quadratec. The bearing was greased heavily before being installed, I cleaned the grease off so I could email the "tech's" from Quadratec pics to try to figure out why it failed. Both inner and outer seals, and new bearing and race are being shipped at no cost as I type.
 
Sorry guys for putting replies to all of your posts into one. Thanks to everyone for the help and questions.

Allen
 
No problem, but I fear the "Crown" brand that did you in before may bring another headache in the not too distant future. Your call, but I'd go to NAPA and get you some Timken's.
Glad to hear Q-tec is taking care of things.
 
I will have to look this through but I thought that the differential oil was supposed to lube the rear wheel bearings.:cool:

IO, I don't have much experience but I read a lot of Jeep stuff. I have seen it reported to drill a hole in the inner seal to let some diff oil bleed in. Superior gives strong emphasis on how to grease a bearing, and how much grease is enough. I also read of guys drilling in a zerc into the bearing housing top, and a zerc-size plug in the bottom. Makes great good sense - take out the plug, pump grease until dirty stops coming out and you see clean grease; put back the plug.

I'm gonna do this next time I repack the rear bearings.
 

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