From the most well - known brand in automotive performance differentials, comes high performance aftermarket ring and pinion sets for performance enthusiasts. Whether you're looking to improve the performance of your vehicle in day - to - day driving or at the track, Eaton's high performance ring and pinion gear sets complement our differentials, helping you get the power to the ground. Eaton's competition series ring and pinion gear sets are made in the U.S.A. from high quality 9310 steel which provides the higher impact resistance needed at the track.