Posi additive question
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Depends on the rear.
USUALLY, 1 bottle is sufficient, but sometimes it takes 2 bottles to smooth out the clutch grabbing/chattering.
I ALWAYS start with 1 bottle and drive it.
Tom Parsons
USUALLY, 1 bottle is sufficient, but sometimes it takes 2 bottles to smooth out the clutch grabbing/chattering.
I ALWAYS start with 1 bottle and drive it.
Tom Parsons
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I have always used 1 and then found a nice parking lot to do some figure 8's in.
Racer
Joined: Apr 2008
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From: PASADENA CALIFORNIA
Tech Contributor
Joined: Aug 1999
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From: Connecticut, USA
With a stock spring posi start with one bottle and see if it hammers,if so add the 2nd. I never rebuild them with the springs and use one bottle,mostly coating the new clutches. They never hammer and lock up tight straight.
Stock posi's that hammer have tight lash and the springs just add to them so they don't slip in turns, just like 4x4 diff's. Add to those the cheaper clutches some use and they will break.
Stock posi's that hammer have tight lash and the springs just add to them so they don't slip in turns, just like 4x4 diff's. Add to those the cheaper clutches some use and they will break.
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Michael S. Palmer
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i don't know of any other way to explain it.. but the additive is a 'friction modifier' which was at one time made of whale oil and became 'extinct' for a while when whales became a protected species. not sure what it is made of now that it's back.
Bill
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Joined: Apr 2008
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From: PASADENA CALIFORNIA
some people say 'yes', some say 'no'; the only way to know for sure is to try the synthetic and see if you get a clutch clatter when you make turns under power. if you get a chatter (and you will unmistakedly know if you do....), then add the 'additive'.
i don't know of any other way to explain it.. but the additive is a 'friction modifier' which was at one time made of whale oil and became 'extinct' for a while when whales became a protected species. not sure what it is made of now that it's back.
Bill
i don't know of any other way to explain it.. but the additive is a 'friction modifier' which was at one time made of whale oil and became 'extinct' for a while when whales became a protected species. not sure what it is made of now that it's back.
Bill
Chris CWPASADENA
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From: Southeast Missouri
The Posi additive is indeed a "friction modifier", and it allows movement between the Posi plates to start gradually rather than holding as stress is applied to the plates, which results in a sudden release and the "snapping and popping" you get otherwise. The old GM stuff came from the head of the Sperm whale, not sure how they manufacture it in these days of synthetic materials.
Racer
Joined: Apr 2008
Posts: 439
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From: PASADENA CALIFORNIA
