The funniest thing - they're not even lined up!!!

 

The service writer told me that their procedure is to line the marks back up and then go just a bit more to set the preload. I'm thinking about shopping around for a mechanic in the Twin Cities that specializes in axles/gears to take a look. I'm **** about leaky stuff on my vehicles and I think they should be able to get this to seal up. The noise from the diff is barely noticable at all.

 

Sounds like you guys might know a few about rear diffs. I want your opinion to a issue with my goat.

It's a 05 gto a4 60,000 miles on it and late last year I bought it from the 1st owner he bought it new and it had 47,000 miles when i got it. The rear end was clunking pretty bad and it had a whine from around 40-50mph or so. Took it a dealer to take advantage of the gm used certified warranty and they drain old diff fluid and put in new gm fluid and the clunking went almost all away it clunks a little every once and a while driving but the whining still there. I think it clunked bad at first because the diff oil was old and never change all the way from new to 47,000 miles. Friction modifier probably was not existence from that old diff oil.

So again currently it has slight clunking but still has the whine noise, I'm reading here about crush sleeve, bearings, pinions and all that, do you think I need bearings and such if so is there a kit I can get with all parts and do it myself?

I am mechanically inclined I just never messed with car diffs before other than basic diff draining and filling. You know what something got me thinking now that I use to have a ford ranger long time ago and it use to whine loud and it ended being bearings in the manual tranny where bad. So I can see where in the gto diff if the bearings are bad the whine can be there. Thanks

 

Good luck OP, I hope you have better luck with these 10 bolts than I have had.

 

Any of you have a link to a write up on the crush sleeve. Right after I got home to the Trans Am I bought while in AFG I put it ona lift and saw the pinion was leaking. Chenged the seal, and am certain I over torqued the pinion nut. I didn't torque it, just beared down on it with a BF Ratchet. Didn't change the crush sleeve because I didn't know to, also didn't know it should be torqued. It whines now, not much, but since I did it right after getting hands on with the car, I'm not sure it wasn't whining before. After reading this I'm sure I need to do this again, replacing the crush sleeve, seal, and properly torquing the pinion nut

 

I would try backing the nut off just slightly to see if it helps