Hey guys....

I've searched the heck out of this, I've seen the FAQ sticky with the list of axle codes but I'm looking to by a rear end from a 90 Firebird and I want to make sure it is from a 1990 so I get the 28 spline axles. Is there a date stamp on the housing or what is the best way to ensure I'm buying a rear with the 28 spline axles?

Thanks...

 

There's no specific date stamp but there is an axle code. It's stamped on the front of the passenger side tube close to the center section. It's not an easy code to find and you need to really clean the diff to read it.

The axle code will tell you what was originally in the diff and since the codes changed every year, it can usually determine what year the diff is.

Now this code will tell you what was originally in the diff but you could still have a 1990 diff that once blew up and a 26 spline carrier (posi) and axles were put into. The only way to be positive it has 28 spline axles is to pull one and count the splines.