ive read a bunch of threads , but can i get a definitive on whether the rear in the 81 needs the GM friction additive? i know im shotgunning the forum with questions.. my eyes are hurting from reading threads.. but im just starting to dig into this new to me vette!  ordering up some service parts tonight

Yes...it has a positraction diff, so you will need the additive.

(post #20,000!)

Joel Adams
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

After you put the new additive in, it's a good idea to find a large, empty parking lot where you can drive in figure eights to work the additive into the clutches.

1973 L-82 4 spd

I was told by a wise ol' sage to do a few figure 8s in reverse also.

Jim Olson 

"The Toys"...!!!  Save the Wave!

Where I've been in a Corvette...!!!

Whoa Babalouie! Is that the 10,000th time you posted that answer, or YOUR 10,000th reply to Any inquiry? 

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Whoops! My bad, the # is 20,000. 

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