C5 Used 3:15 Ratio Automatic Differential Carrier 1997-2004

What is the difference between a 1-rib and 3-rib differential carrier?

If your Corvette is a 1997 to 2000 model with the original differential, you'll find it housed within a 1-rib casing. The transition to a 3-rib case began partway through the 2001 Corvette model year. Not all models from 2001 feature this design, but every C5 Corvette model from 2002 to 2004 does.

The addition of the extra ribs significantly enhances the rigidity of the casing. This reinforced structure reduces flex and distortion under extreme pressure conditions. The result is a differential that maintains better internal alignment, which, ideally, reduces susceptibility to deflection and damage.

GM part number: 12556313