Stupid question but, I raised the rear on my GTA the other day and I noticed that if I spin the drive wheel one way...the passenger one (and vice versa) spins the same way. I always though due to the differential that the 'other' wheel should spin the 'other' way.
hmm, Is my rear end shot? Oh, it's a 9bolt 3.45 rear.

 

Sounds like it's working perfectly normal for a posi rear.

 

 

It will only differentiate around corners.

 

It's definatly NOT a torsen posi unit
You've got a clutch posi, when you change diff fluid make sure you add the additive!!! Unless you don't like your posi.
Do a burnout and check for 2 lines of rubber.

 

It's a 9 bolt so it's a cone style posi unit (technically still a clutch, but to most people a clutch is disk style). To check if the posi is working correctly, it should take ~ 40lbft to rotate the tire (when the other is fixed). Anything less and the posi is getting worn out.

Miles
Diff Solutions
www.9bolt.com

 

yeah sounds like you have a posi rear end..

 

Nope that rear end is shot!!! Lemme take it off your hands real cheap-like!

 

Yeah Steve...ahem...that rear is gonna go on you anytime.....ahem...I've got this 10 bolt here that spins great in both directions...ahem...trade???


Ed, with envy of an '89 3.45

 

Hey Miles, any way to check if a posi is good when the diff is out of the car?

Thanks..Ed

 

Same way, just lock one of the axles and put a torque wrench on the other.

If it's just the carrier, then insert a pair of axles.

Miles

 

Should both wheels move?

Im about to take the rearend out of my 88 parts car(9-bolt disc brake 3.27) and put it in my 91 Formula.

With the car off the ground I can spin the left wheel easily, but the right wheel is tougher. But if Im spinning one wheel, shouldnt the other wheel spin the same direction?

Thanks