I'm not sure of im right but don't ALL z28 93-02 have Posi..?

My friend has a 94 Z28 and he said he doesn't have it, and was going to switch out the rear end with something else.

And now today i went to do a burn out and i think (not sure) that i only did a one wheel burn out, beacause i'm pretty sure i only saw 1 line of rubber in my rear view mirror but i'm not sure. When ever i go straight from a stop it will just spin the tires and go straight and not kick out the the left or right..

I'm also not sure when the deff. fluid was last change so do you think i might try and give that a try?

 

Yes...all Z28's came from the factory with Limited slip differentials(GM positraction). However...they do wear out over time, and the result is what you are describing...it starts acting like an open rear. Its a good idea to change out your rear axle fluid with some synthetic gear oil (dont forget the GM limited slip additive!).