I just got my posi from SLP and its gonna go into my 91 Z28. I know the posi is a 3-series carrier. I just wanna make sure my rear is a 3 series. And if im not mistaken it has 3.23's in it too, right? Its the car in the sig, has the G92 option and all. I may also upgrade to 3.42 gears, which bringsmeto ask what speedo gears would i need to calibrate from the dealer. Thanks in advanceguys.

 

There is exactly one way to be certain what's inside your rear end, and it doesn't involve codes.

Take off the cover and look.

Even if you can find and decode the codes, if your rear has been swapped or worked on, they could be wrong. It's a whole lot less trouble to take off the cover and look than to buy a bunch of stuff, then take off the cover, and discover that you don't have what you thought you had; then you're set back however many days it takes to get new stuff in, it costs you freight 7 restocvking charges, etc.