How to Choose the Oil and Fluids for a GMC Sierra
- 1). Use Delco Supreme 11 brake fluid or a DOT-3 equivalent to maintain your stopping power. If you're using your vehicle for off-road racing or other high-impact uses that may require a lot of braking, consider using a specialty brake fluid to prevent boil over.
- 2). Maintain your 5-speed transmission's hydraulic clutch system with hydraulic clutch fluid, GM part number 12345347 in the U.S. and 10953517 in Canada, or use a DOT-3 equivalent brake fluid. The 6-speed transmission requires a different clutch fluid, GM part number 88958860 in the U.S. and 88901244 in Canada, or a Super DOT-4 equivalent.
- 3). Refill your power steering fluid reservoir with GM power steering fluid, U.S. part number 89021184 or Canada part number 89021186.
- 4). Change your DEXRON-III automatic transmission fluid regularly if you have an automatic transmission. You can also use this transmission fluid in the GMC Sierra manual transfer case. If you're running a manual transmission, see Tips below for information about manual transmission fluid.
- 5). Lube your rear axle with an SAE 75W-90 synthetic axle grease. If you have a steerable rear axle, it's vital that you don't add a friction modifier. For the front axle, use an SAE 80W-90 axle lubricant.