Occasional clunking in the back end

moes

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Did they use a friction modifier?

oil.jpg
 

Ron H

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Try putting car in neutral before slowing to turn to see if the clunk goes away. Possibility of the trans downshifting noise. Check u-joints on driveshaft. Could be the lash wasn’t set properly as another possibility – sure grips are a trick compared GM/Ford posi’s. Adding gear additives are vital as posted. Rear end guru suggested GM additive, other’s have said Ford. I’ve used mopar so went with GM on the last change…can’t tell any diff…(pun here?). Just a few quick toss overs.
 

khryslerkid

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Try putting car in neutral before slowing to turn to see if the clunk goes away. Possibility of the trans downshifting noise. Check u-joints on driveshaft. Could be the lash wasn’t set properly as another possibility – sure grips are a trick compared GM/Ford posi’s. Adding gear additives are vital as posted. Rear end guru suggested GM additive, other’s have said Ford. I’ve used mopar so went with GM on the last change…can’t tell any diff…(pun here?). Just a few quick toss overs.

Any friction modifier will work. Cass told me once that they did some kind of testing and the Motorcraft came out on top for lasting the longest. FYI
 

Cranky

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Any friction modifier will work. Cass told me once that they did some kind of testing and the Motorcraft came out on top for lasting the longest. FYI
Never had any problem with the Mopar additive.....and that's what I have in my truck right now.
 
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