DOC4444 wrote:
Well, it's either incorrect pinion depth or a bad pinion bearing. In any case, it's life is rapidly coming to an end. I assume you did not have a leak and run it out of hypoid oil. Before you push the dealer to be more "specific" about the "suspicious" rear end parts and get them to make notations that will kill any chance you might have of ever getting another dealer to fix it under warranty, I would get it out of there and try another dealer.
If the diff really has non-factory parts, you can forget about a warranty repair. If that is out, I would pull the center section and take it to a good 4WD drive shop that rebuilds diffs all day long for evaluation. If you need a new R&P, a good used center section is probably the way to go. This is also the time to consider a Detroit TruTrac.
We had our rear diff recently totally rebuilt twice in the past three months under warranty. (The Nashville Jeep dealer screwed up the pinion depth.) Dealer pricing is about $1200 for all the parts (R&P, bearings, seals shims, etc, everything except LS clutch pack) and about $800 for labor.
If your R&P is OK, bearings, seals, etc., and labor should be under $600 at a local 4WD drive shop if you bring them the center section so they are only doing bench work.
DOC
You either have to pull the whole diff out or just bring the whole vehicle in,the 8.25 has no center section to pull out like a Ford 9" does(3rd member).Cost is the same for the rear axle either way you bring it in,it's the front axle that cost goes way up in a KJ due to being IFS.