Which is a better Rear End?

[HasselZ28]

I need to get a new rear end because I blew mine up. I'm considering either the performance axle with the 3.23's or I'm looking at an axle with 3.42's. Now I know the taller gear would be nicer but what fbodies came with the 3.42's with POSI? And is it better than the 3.23 axle? All help is greatly appreciated!

[Wesman]

I need to get a new rear end because I blew mine up. I'm considering either the performance axle with the 3.23's or I'm looking at an axle with 3.42's. Now I know the taller gear would be nicer but what fbodies came with the 3.42's with POSI? And is it better than the 3.23 axle? All help is greatly appreciated!

The axles are all the same (10 bolt, 7.5") regardless of the gear ratio. Any axle you find with a 3.23 or 3.42 ratio will have a posi unit, because those ratios were only used in V8 equipped cars and all V8 cars had a limited slip rear.

All 6 speed manual cars came with the 3.42 posi rear. The only cars that came with the 3.23 were automatics with the SS/WS6 performance package. Automatics without the performance package had the 2.73 ratio rear.

Also be aware that there were two different kinds of limited slip rears. The 98 and 99 F-bodies had an Auburn clutch type limited slip, which uses clutch packs to limit the speed difference between both wheels. The 00-02 cars have Torsen limited slip units, which are are "torque sensing" differentials, hence the name. They vary torque side to side based on available traction using gears instead of clutch packs. However, the Torsen is useless if one wheel has no traction, since it can only multiply torque from one wheel to the next, and if you multiply 100% traction on one side times 0% on the other side, you still get zero ;)

[HasselZ28]

thanks thats some good info, so the auburn is a better posi right

[Hi-Po]

Heres a good read for some generals!
http://www.ls1.com/forums/showthread.php?t=7748

[Wesman]

thanks thats some good info, so the auburn is a better posi right

Not necessarily. More a matter of preference.

The torsen is nice because it has no wearable components, but the auburn is a true limited slip as opposed to being a torque biasing unit.