I just came back from test driving an 04 1500 reg cab with Hemi.When putting to the floor i heard a funny sound like a prolonged ping from the rear end but as the speed picked up it went away.It has a 3.92 antispin rearend.
Any ideas?

 

I would guess a clutch pack retaining clip has come loose, without a visual inspection of the rear differential I'd be a little apprehensive.

 

Is that a easy fix,i have never opened one of these before?

Is there a permanent fix

 

Yes, provided the clip hasn't done any damage (if that's what it is, but it's really the only known issue in the AAM 9.25" rear end), you can simply pull it and any fragments out, inspect the other clips, put in new fluid and call it a day.

Some prefer to just yank ALL the clips, they are only in there to keep the LSD clutch packs in place while setting the ring & pinion. But the stock LSD isn't a very good one and most opt to just replace the whole damn thing with either an Auburn Gear LSD or Detroit TruTrac both of which have a much higher bias than the stock LSD and "lock up" better.

A loose "C-Clip" wouldn't by any means be a deal killer IF it hasn't chewed up the ring & pinioin or spiders yet...

 

Thanks for the info,it is a one owner truck with 147k on and is quiet and solid overall just the rear sound and it was only breifly in the lower gears. Will let you know if I need more tech support!!

Thanks

 

Does anyone have a pic of the rear opened and where the C-clip goes?

 

I'm on my phone and can't do a search, but do a search of the 3rd Gen technical section, you'll probably find a hundred pics...