Speedmaster PCE204.1065 GM 8.5" 8.6" 10 Bolt 30 Spline Clutch Plate Type LSD Limited Slip Differential

The GM 8.5" 10 Bolt axle, also known as the GM 8.6" axle or GM 10-Bolt, is available in many front and rear axle applications including both solid axle and IFS / IRS configurations. While the GM 8.5" axle features an 8.5" diameter ring gear and the GM 8.6" axle uses a slightly larger 8.6" diameter ring gear, almost everything within the axles is completely interchangeable. For 8.5"The factory 8.5" carrier when installed in a factory 8.5" axle uses Timken bearing part # LM501349 and race part # LM501314.The inner diameter of the bearing is about 1.625" and the outer diameter of the race is about 2.890".For 8.6"The factory 8.6" carrier when installed in a factory 8.6" axle uses Timken bearing part # LM603049 and race part # LM603012.The inner diameter of the bearing is about 1.780" and the outer diameter of the race is about 3.060".Special Case:When retrofitting an 8.6" carrier (or a locker or a spool or any device that replaces the carrier) into an 8.5" axle, it uses Timken bearing part # LM102949 and race part # LM102911. Essentially, it's an ID of 1.780" (bearing) and an OD of 2.