Although my friend told me 1989 I did his vin code and it says 1990. Which rear end came on the RS for these years? I mean like what are the spline count? etc? Thanks!

 

90 rear should be 28 spline, i think that was the change over year from 26, but some people say that it went to 28 in 89 and some say that select 89 camaros got a 28 spline rear. So if it is definately a 90, then it is 28, all i know for sure.

 

Agreed. 89 is a possible 28 spline but more likely 26. 90 is a 28 pline. Unless for some strange reason it had a 89 diff installed but isn't likely but from your conflicting years are it's hard to say.

 

Thanks for the info...now just have to decide what gears to throw in....