some quick questions:

what size rears came with a posi? both camaro and firebird
did 2.77 come with a posi?

also, what size rear does a 4wd blazer have...like made in 85

 

More than likely it has the posi because that's the Borg Warner 9 bolt. Those usually came with posi. The only sure fire way to tell...... well there are actually two ways to tell. 1) RPO code. If it's a G80 you got posi. 2) Lift rear end off the groung (both tires) and spin one wheel. If the opposite wheel spins the other way, you don't have posi. If it spins the same way, you do.

If you mean numerically gears....... you need either the RPO code or the axle code on the axle housing. If you mean diameter, it's a 7.5".

AJ

 

thanks

just to get my facts straight, no 2.77 came stock with a posi right?

whats the formula to find out gear ratio?

 

99+% of all 2.77 ratio borg warner 9 bolt 7.75 rearends were posi units.

Miles
Diff Solutions
www.9bolt.com