High performance Yukon Ring & Pinion gear set for GM 9.25" IFS Reverse Rotation in a 4.56 ratio. Yukon exclusively uses 8620 steel in all their Ring & Pinion sets for high strength and long life. They use the latest designs and manufacturing technologies to provide a quiet running gear that is strong and easy to set up. All Yukon Ring & Pinion sets come standard with a one-year warranty.