64 positraction problem
Thread Starter
Cruising
Joined: Feb 2012
Posts: 11
Likes: 0
From: Orange Beach Al.
64 positraction problem
HELP--- just had carrier bearings replaced, and now have horrible noise after( heat-up) 50-60 miles, sounds like posi is trying to lock up, only occurs in turn mode, drove straight for 100 miles with no issue, exit interstate and it begins , Seems to get better if put in reverse then forward but have to "drive-thru" vibration and noise from rear-end.
Stops when cooled off, any ideas would be appreciated.
Thank you Gary
Stops when cooled off, any ideas would be appreciated.
Thank you Gary
Drifting
Joined: Apr 2011
Posts: 1,668
Likes: 414
From: Australia
HELP--- just had carrier bearings replaced, and now have horrible noise after( heat-up) 50-60 miles, sounds like posi is trying to lock up, only occurs in turn mode, drove straight for 100 miles with no issue, exit interstate and it begins , Seems to get better if put in reverse then forward but have to "drive-thru" vibration and noise from rear-end.
Stops when cooled off, any ideas would be appreciated.
Stops when cooled off, any ideas would be appreciated.
Try some GM posi additive, or suck it all out and replace the oil with correct "limited slip" diff oil. It takes about 2 quarts.
I used some Valvoline I had lying around when I fixed mine, but there's probably better oils around.
You'll get a few suggestions, but that's probably all it is.
Good luck
Burning Brakes
Joined: Mar 2012
Posts: 987
Likes: 171
From: Kingwood Texas
Had exactly the same problem after a bearing and ring and pinion change. Same symptoms; only occurred after highway driving, a stop, and then a turn. Believe the posi was locking up and had to disengage in turn. Car was also squirrelly in long , gentle highway curves. Tried changing fluid and adding 2bottles of GM limited slip additive. No help. Finally replaced posi with a new Eaton unit and problem solved. Apparently, clutches were locking when heated up after several miles of highway driving.
Hopefully, lube and additive fix your problem.
Hopefully, lube and additive fix your problem.
Race Director
Joined: Apr 2005
Posts: 11,308
Likes: 2,160
From: Bowling Green, Kentucky
Sounds like a classic case of "wrong oil" in a GM posi.
Try some GM posi additive, or suck it all out and replace the oil with correct "limited slip" diff oil. It takes about 2 quarts.
I used some Valvoline I had lying around when I fixed mine, but there's probably better oils around.
You'll get a few suggestions, but that's probably all it is.
Good luck
Try some GM posi additive, or suck it all out and replace the oil with correct "limited slip" diff oil. It takes about 2 quarts.
I used some Valvoline I had lying around when I fixed mine, but there's probably better oils around.
You'll get a few suggestions, but that's probably all it is.
Good luck
I would drain all the old lube and then install 80W-90 conventional lube for "limited slip" differentials PLUS add 1 or 2 of the small GM bottles of posi lube. Try one bottle first, and add the second one if needed. Then go out and run the car and make some figure eight turns.Larry
