posi rear

[band77one]

so i may be buying a posi rear from cody soon, but its the 9bolt gm , i have the 10bolt gm rear. cody's has 2.77 gears and mine has 3.08's. is this a good swap ? i plan on getting 3.73 gears and a heavy duty differential cover either way

[V]

as far as i know, it is quite difficult to get aftermarket gears for the borg warner 9 bolt rear. The largest oem gears are usually what everyone runs in those and those are 3.45s. When i upgrade my SS rear i'm just going to a ford 9", larger choice of gears sizes, easier gear swaps(3rd member) and stronger than the 9 or 10 bolt GM rears.

Also with your 10 bolt - 9 bolt swap, I am pretty sure all OE 9 bolts were disc brakes, and very few 10 bolt had those, in that case youd need to change the proportioning valve too, along with the gears for the speedo drive so your speedo will be correct.

[90FormulaWS6]

IMO i would go with a 10 bolt, because theres more parts available for them, if you plan on doing anything go with a series 3 carrier w/ 28 spline axles

[Tru2Chevy]

The 9 bolt is a stronger rear, but good luck trying to find a good set of gears and AFAIK there is no aftermarket diff. cover available for it. Unless you are planning on some crazy engine build, I would spend the money on building up your 10 bolt to handle some power.

- Justin

[Batman]

TA 1802, 9 bolt diff cover from TA performance
http://www.taperformance.com/rearend.htm

[Tru2Chevy]

TA 1802, 9 bolt diff cover from TA performance
http://www.taperformance.com/rearend.htm

Nice! I'm sure that's gonna make a lot of third gen guys happy.

- Justin