I was wondering what type of differential my 1991 Camaro Z28 has, since its a 305

 

should be a posi

 

No way to tell unless you pull the cover and look. I''l guess open diff and 2.77 gears.

 

Well, if its positive, does dat mean both my rear wheels will turn, (peel off at the same time)?

 

Not necessarily. Only way to tell is to pull the cover and do some proper maintenance, since i bet it never has been done. No matter what people tell you about little trick and way to find out if its a posi, are all myths, wivestales and mostly bull****.

 

The only way Ill find out, if I step on it... I just acquired this camaro, last week-end

 

Ok think whatever you want.

 

Do it, and leave two patches, and think you have a posi, but before you go off and tell everyone it is a posi, remember its entirely possible to get both tires spinning at the same time even on an open differential (non-posi).

Before you do anymore driving, go buy two quarts of gear oil, and rip the differential cover off. You need to change that fluid anyways. Then spin the differential around until you can see inside it to see if it has a posi. Next step is to spin the differential around until you see markings on the ring gear that say something like "15:41" or "13:42"

Divide the second number by the first number to get the gear ratio.

 

My bet is a limited-slip posi unit running around 2.73 gears. Your axle code should be on the front face of the right hand axle tube about three inches from the differential cover. Be prepare to wipe away a lot of dirt and grime though. There will be eight characters stamped there. The first three should be your axle ratio, the next number or letter will tell you who made your rearend, the next three digits will tell you the year it was made and the last digit tells you what shift it was made on. You can check on this site to find out which axle ratio you have, or if you want to post the code, I'll tell you.