System Specifications

FRONT AXLE (1500 SERIES)
SAE 80W-90 Axle Lubricant (GM Part No. U.S. 89021671, in Canada 89021672).

FRONT AXLE (1500 HD, 2500 HD, and 3500 HD SERIES)
SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 89021677, in Canada 89021678) meeting GM Specification 9986115.

REAR AXLE
SAE 75W-90 Synthetic Axle Lubricant (GM Part No. U.S. 89021677, in Canada 89021678) meeting GM Specification 9986115.