BRAND NEW 30 Spline internal Spyder and side gear kit for 10 Bolt GM 8.5" OPEN Differentials from 1989 - 1998. Kit includes (2) Spyder Gears with thrust washers, (2) Side Axle Gears (30 Spline) with thrust washers, (1) pinion shaft (cross shaft or pin to some of you) and the locking retaining bolt. This has 30 spline axle gears for the 1989 thru 1998 GM 10 Bolt 8.5" rear. These rears are found in various GM vehicles like 1500 Chevrolet and GMC pickups and FULL SIZE SUV's such as Tahoe and Yukon and 1500 Suburbans from 1989 thru 1998. NOTE: This set will NOT work in 1988 and earlier as the earlier models were 28 spline axle gears and all gears are of different size in the early models. THESE ARE NOT FOR G80 FACTORY POSI UNITS, THESE ARE OPEN DIFFERENTIALS ONLY, MAKE SURE YOU KNOW WHAT YOU NEED AND WHAT YOU ARE BUYING! These fit what we describe.HAPPY MOTORING!