Rearend Problem?
Thread Starter
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Joined: Oct 2003
Posts: 67
Likes: 1
From: Renton Wa.
Rearend Problem?
I have a 90 with manual trans. I was pushing the car afew feet today in the garage and heard a clunking noise from the back of the car. I grabbed one wheel and moved the car again and I could feel the clunk through the rear tire from both sides. Doesn't happen all the time in the same place during rotation, but it is repeatable. Anyone have problems with the posi unit clunking in these rearends? 
Should I worry about it since I didn't feel it while driving?
Should I worry about it since I didn't feel it while driving?
Melting Slicks
Joined: Oct 2004
Posts: 2,662
Likes: 8
From: Knoxville Tennessee
This is just a wild guess, but on other cars with posi-traction rears; when the posi additive wears, the clutches start grabbing and causes a clunking sound. Try changing the diff fluid adding back the correct fluid and additive and see if that solves your problem. If it still clunks you can progress further. This is what my 79 did and what I did to solve the problem. I hope it solves yours too.
Bernie
Bernie
Race Director
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Bernie is right about the clutches making noise when the fluid gets old, but I wouldn't be changing the fluid unless you hear it while driving. You could jack the car up and check the posi.
RACE ON!!!
RACE ON!!!
Melting Slicks
Joined: Jul 2006
Posts: 2,151
Likes: 0
From: Strongsville Ohio
dont ignore it though, my brother has an f-150 and had the same thing went from a noise, so i put the ford rear end additive in, to then a virbration when turning, added the additive again. to 6 months later buying a new WHOLE rear axel and tranny box, clutches were gone, gears where shot rear trashed. be careful. but try and figure it out...also the truck is no vette but just my experiences.
