[C2] Posi-track fluid usage???
Thread Starter
Le Mans Master
Joined: Apr 2001
Posts: 9,556
Likes: 288
From: Granbury Texas
Posi-track fluid usage???
How much posi-track fluid (friction modifier) goes into one 4 series pumpkin to add to the stock amount of GM Staylube GL4? Is that amount the same for a 3 series pumpkin?
Thanks,
Thanks,
Race Director
Joined: Apr 2005
Posts: 11,277
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From: Bowling Green, Kentucky
Most start with one bottle, but wind up adding a second bottle before it's finished. 
Race Director
Joined: May 2000
Posts: 12,712
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If you don't want to burn up the ring and pinion you better use nothing less than 80W-90 GL-5. You may be able get away with GL-4 in a manual transmission, but the EP additives in GL-5 (what give it the pungent odor) are absolutely necessary for the axle if you want it to live.
I can't believe no one has brought this up.
As I've posted many times before the original spec for BOTH manual transmissions and axles from the era was Mil-L-2105D. (Check the owner's and service manual if you don't believe me.) The mil-spec was canceled about 20 years ago and replaced with SAE 80W-90 GL-5.
Don't come back with the GL-5 "corrodes yellow metal myth". It's total BS.
Duke
I can't believe no one has brought this up.
As I've posted many times before the original spec for BOTH manual transmissions and axles from the era was Mil-L-2105D. (Check the owner's and service manual if you don't believe me.) The mil-spec was canceled about 20 years ago and replaced with SAE 80W-90 GL-5.
Don't come back with the GL-5 "corrodes yellow metal myth". It's total BS.
Duke
Last edited by SWCDuke; Aug 23, 2017 at 03:30 PM.
Race Director
Joined: Apr 2015
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From: Fresno California
I've run non-GL-5 in everything I own for decades and haven't had any failures with ring and pinions except for the one time I ran a rear end dry of oil due to an unseen leak. I agree that GL 5 is harmless to yellow metals. Not one actual case has ever been presented in real life. Not one.
