[updated:LAST EDITED ON 30-Apr-02 AT 07:16 PM (EST)] I have asked this question before here but did not come to a solid conclusion....anyway here goes, So i have money down on a truck,(a 76 highboy) and the only 2 problems i can find are a motor mount that has rotted out and this rear end problem. The rear end (dana 60 non posi)whines when i let off the gas....it was originaly a posi rear end but the guts where replaced when the carier went out. the guy who rebuilt it swears up and down that the whining is a differental shim holding the ring gear to tight to the pinion...The last person I talked to here said it WAS the bearings, nothing else. Is this right? There is less than 300 miles on the rebuild he did and I just wanna know if im lookin at rebuilding a whole rear end or just re shiming this one? Anyway I will buy the truck either way, its a simple matter of how pissed the wife will be... HEHE more money into a 30 year old truck I just bought and LOVE! + My wife = Me on the couch!
Thanks for the help!

 

whine on decel is must likely an improperly setup ring and pinion

 

so this IS most likely a SHIM issue on the differential holding the ring gear too tight to the pinion...Correct?

 

It sounds like a shim to me also. Pull the cover and check the wear pattern or use gear goop to be sure. :-X12

 

J,
There are a few things you can do to check your problem.
1. Get the rear end off the ground.
2. Grab the drive shaft and turn it back and forth.
You should have upto a 1/4" "LASH" in the driveshaft. A rear end will "HOWL" when the lash is too tight. This means that there will be no "LASH" when you check it. Changely enough, rear ends only "HOWL" when under load/power. If your rear end is "HOWLING" off power, I would check the lube levels ASAP. When you pull your finger out of the hole be careful to look for metal flakes. This will give you an idea of the trauma that has taken place upto this point.
NOTE: When you remove the shim from one side put in back in the other side. This will keep your overall side to side dimension the same.
Keep us up to date on your discoveries,
KingFisher

 

Thanks for the help...I will let you know what happens.