Duragrip Positraction Unit, GM 8.5 & Ring and Pinion, 3.73 Ratio

Differential Carrier The Yukon Dura Grip provides aggressive yet smooth traction to give you the confidence and performance you need. Get longer life and better traction with the heavy duty Yukon Dura Grip Positraction.  Fits GM 8.5" with 28 spline axles. 2.73 ratio and up only. 4-spring, clutch style positraction. Internal gears are manufactured using forged 4320 steel and cut to provide stronger teeth. Fully rebuildable. Assembled in the USA. Yukon recommends the use of high grade GL-5 gear oil and Yukon LSD (Limited Slip Differential) additive for long life and smooth operation. Part number OILADD. The use of synthetic oil is allowed but may result in aggressive or noisy operation. This unit requires use of carrier bearing & race part numbers LM102949 & LM102911. Ring and Pinion Many 8.5 Inch ring and pinion ratios to choose from. 8.50" diameter ring gear. 1.625" diameter pinion. For rear axle application that uses 10 ring gear bolts & 10 cover bolts. 30 pinion splines. Uses LH thread ring gear bolts - 7/16"-20 such as 5502092G. 3.73 Ratio.