I had a truetrac and gears put in my front diff early last summer. since then I would get a strange vibration sound sometimes when it was in it was if 4x4. it sounded almost like the shaft rattling in the diff. I spent a while looking for the problem last summer, then figured it was the truetrac possibly not machined correctly so I replaced it with an arb(was going to do that anyway). the noise was still there. I ran that for a bit looking for the problem, then had one of the axle tubes leaking so I pulled the shaft out, and it had a small ridge about where the seal would run. threw in a new shaft thinking possibly it was just a fluke, and it has done the exact same thing in very short order. I also pulled the passenger side, and it is getting the groove also.
the groove is also not exactly round on the shaft. some spots are deeper then others.

could this be a setup problem?? I have 2 new shafts again, that I would like to use, but would like to figure out the problem before i ruin them.
any other suggestions would be appreciated also.

What kind of axle? A little more info, maybe someone could help. :confused: Blindly, I would make sure the tubes are straight before sticking new anything in there.

Bent axle tube, possibly ?

it is a d30 hp out of my 98 cherokee

Sounds like a bent housing. Good way to kill an ARB.

one more thing that I noticed is that the seals appear fine, with no visible signs of wear, but it is definately where the seals ride on the axle. strange that it would be able to groove the axleshaft, yet not tear up the seal.

one more thing that I noticed is that the seals appear fine, with no visible signs of wear, but it is definately where the seals ride on the axle. strange that it would be able to groove the axleshaft, yet not tear up the seal. Yep, the same way a crank can get ruined from a rear main seal :(