Interesting bearing experience...

[Diagram14]

So I bought my 4rnr some 4-5 months ago and realized shortly thereafter that it had a bad bearing (rear drivers). I got the parts and pulled the shaft to have the job done by the mechanic my family has been taking vehicles to for the last 11 years. He does the job, it looks good and I put it all back together after replacing the inner seal.

Everything was golden for about two weeks when my new brake job started sticking again. So I pull everything back apart and find an excessive amount of play in my 2 week old bearing. Now Im pissed because the only explaination is that my mechanic botched the job. I took it to a differential shop because Im scared to trust anyone but a specialist and the dealership quoted me two prices "because we dont know how hard it is going to be."

In the end we found that a previous owner had run a bad bearing for so long that at some time it had heated the bearing hub to point of expansion. When he got it all apart the Diff. Guy had me come in and showed me ho he could just tap the new bearing into the hub as if he were just knocking on my front door. The fit was so loose that my gear oil was passing around the bearing and into the drum via the hub.

The new used hub seems to be doing the job so far. Additionally, I had a shake from about 50mph + that appears to be gone since the placement of the new hub. Maybe my experience is one-of-a-kind, but I will never not keep that hub in mind when doing a bearing job again. I hope this helps at least someone out there...I had to pay for it twice.

 

[CO_FlyFisher]

Um, not sure where to start here.

First, the bearing should not be terribly tight in the "hub" (the drum backing plate), not to say yours might not have been looser than normal. The bearing does have a VERY tight press fit onto the axle however. Second, the inner seal should be keeping the diff fluid from ever getting that far in the first place, unless your "hub" was REALLY out of whack (enough that driving on it would have been a big problem). Last, the bearing is not a sealed type, so it won't keep the diff fluid out of the drum, thus the requirement of the inner seal (the bearing just has a plastic cover plate on one side that easily pops off).

I hate to say it, but I think either you might have messed up the inner seal replacement when you did it, or you cut the seal when you replaced the axle shaft into the housing (that is easy to do if you're not careful).

edit: I didn't realize you were so new. Please excuse my missing that first sentence in your post. Failing rear axle seals are common on the 3rd gen, and unless you've read through the tons of these threads already, my guess is that is/was your real proble.

 

[Diagram14]

Correct. The hub was so far gone that there was play between it and the bearing. That same play was enough to compromise the sealing ability of the inner seal. Additionally, one of the bleed points of oil into the drum was around the bearing (between the bearing and hub), not through it. Call me crazy but the same bearing and seal job with a different hub and my problem has been resolved.

 

[CO_FlyFisher]

If that was the case, then I don't doubt that a new "hub" fixed you up! I can't believe you didn't have more problems with the rearend though. Loose bearings can be really bad!