Im trying to install a posi out of a 89gta into my 86 z28, Im not real sure what is going on but i have way too much backlash, so much that shims arent going to fix it. Here is what i did and this is prob my mistake but i want to know for sure, i left my pinion gear that was origianlly in the car in place and took the ring gear off my old open rearend, which was in the car and put it onto the new posi. I am guessing the ring gear that was in my car isnt made for this carrier even though it bolted right up? help me out guys, a ring gear came on the posi when i bought it and ive tried putting that ring gear in with my pinion and its the same thing... way too much backlash. I think i might have to get a new ring and pinion made for this carrier, am i right?

 

how can shims not fix it? you don't increase the total shim thickness, you only change the arrangement from side to side to increase the shim thickness on one side and decrease it on the other

 

ive tried putting bigger ones on the drivers side and smaller ones on the pass side, the thickness is still the same as the original ones howeverit still isnt tight enough

 

I have a feeling that the two carriers are different series. To check place both carriers upright on a bench with the passenger side bearing up (the ring gear teeth would also be up).

Look at the flange the ring gear bolts to, both carriers need to have that flange at the same height. If not then they are two different series carriers. The two would be 3.23 and up, and 3.08(?) and down (such as 2.73).

RBob.

 

didn't think about the carriers series not matching the gear set. you might need a shim for the ring gear.

 

thanks guys, i will check that out tonight, if that is the case where would i get a ring gear shim? and how do i know how thick it should be?

 

I believe its .25" difference between a 2 and 3 series carrier.

 

What gears did you take the ring gear from to install w/ the existing pinion? Are they the same?