Yukon Gear & Axle (YSPPN-016) Pinion Nut For GM 12 Bolt Car & Truck, 55-62 Car & Truck, 8.2", 8.2" Buick/Olds/Pontiac & 63-79 Corvette. 1 1/8" Socket, 7/8" X 16 Thread. 1 Year Warranty High Quality Small Parts Engineered to Fit Specific Differential Applications