I've been looking and looking and looking for the right ring and pinion, I have a 91 RS camaro, I do believe the rear axle is stock, doesn't look like any one has done anything with it, the engine and the transmission was stock when I bought the car.

since my rear axle is stock, is it for sure 10 bolt, 7.5 and 28 spline?
I can find 10 bolt, 7.5 but not a 28 spline, either 26 splines, or 27 splines, but not a 28 anywhere.

I'm also finding that either a 26 spline or 27 spline ring and pinons will work with camaros : 1982 - 2001.

and I'm having a hard time believing it.

and while I'm asking, what would I need for series? a two series or a three series? I believe that I have 3.08 stock ring but I could be wrong.

I want to put either 4.11 ring gear or a 4.10. which ever one is gonna work.

how about posi tractions? 28 spline and what series?

Thank you,
Tim

 

26/28 spline is the splines on the axle. The ring and pinion doesn't care how many spines are on the axle. The splines on the pinion are all the same for the 7.5" diff.

7-1/2 and 7-5/8 gears are the same. Even though GM increased the OD of the ring gear around 1986 to 7-5/8", many people still refer to these diffs as 7.5". A 7.625" ring gear will still fit on a 7.5" carrier.

Since your car will have 28 spline axles, if you buy a new posi, it will need to be for 28 spline axles. If you're going to use 4.10/4.11 gears, you'll need a 3 series carrier. I can't remember if 3.08 gears are on a 2 or 3 series carrier.

 

The 3.08 in the 7.5 rear end is on a 2 series. You will need a 3 series posi for the 4.10 gears. I recommend the Eaton posi for street/strip use. If you will be auto cross or road racing then the Torsen or Truetrac would be better.