I need to replace the rear axle cover and need to find what rear that is in my '13 Silverado 2500 HD. It is 14 bolt but don't know if it is 10.5 or 11.5. Is there a way to tell from specs on the glovebox door? Thanks in advance.

 

Look for the codes that start with GT - that will give you the gear ratio and ring size can be determined from that.

If it’s a dually chances are good it’s an 11.5.

 

https://www.randysworldwide.com/diff...tification-gm/