Ok i have a 1992 V6 firebird now is it an open or a lSD (what ever GM wants to call it) because i know if you have a open then one wheel is pushing the car and when u burn out only that wheel the drive side spins but i sometime burn out both tires and sometime one or the other i just need to know waht the stock rear end is and the gear ratio its a 10 bolt rear i think and how much fluid do i full it with about to get a tune-up so just need to know.

 

Unless the previous owner changed it, the axle would have an open differential in it. I believe the '92 V6 automatics received a 3.23 rear gear ratio.

As for fluid, you'd fill the diff through the plug in the top of the pumpkin (a 3/8th ratchet fits right into the plug, no socket needed) until the fluid starts coming out of the hole. Fill it right to the top; mine takes about 1 3/4 full bottles of gear oil. If you had a posi, you'd have to put posi additive (buy from GM parts counter) into the axle first. Oh and beware, the rear gear fluid smells AWFUL.

To check for posi, you'd have to jack up the rear of the car safely, and turn the driveshaft (not the tires!) by hand. The wheels will start to turn forward. Now have someone else try to stop one wheel (or if you're under the car safely, reach out and put your foot on one tire). If it's a posi, both wheels should keep turning forward. If it's open, the one wheel will stop while the other keeps going.

Or you could have a posi that's burned out its clutches, in which case, that means you basically have an open diff again.

 

-.- a open damn it guess i can win any burnout contests then lol