2008 GMC Sierra 1500 Pickup Owner's Manual - Page 440

• To check the parking brake's holding ability: With the engine running and the transmission in NEUTRAL (N), slowly remove foot pressure from the regular brake pedal. Do this until the vehicle is held by the parking brake only. Recommended Fluids and Lubricants Fluids and lubricants identified below by name, part number, or specification can be obtained from your dealer/retailer. Fluid/Lubricant Engine oil which meets GM Standard GM6094M and displays the American Petroleum Institute Certified for Gasoline Engine Oil Engines starburst symbol. To determine the proper viscosity for your vehicle's engine, see Engine Oil on page 5-13. 50/50 mixture of clean, drinkable ® Engine Coolant water and use only DEX-COOL Coolant. See Engine Coolant on page 5-23. Hydraulic Brake Delco® Supreme 11 Brake Fluid or System equivalent DOT-3 brake fluid. Windshield Optikleen® Washer Solvent. Washer GM Power Steering Fluid Power Steering (GM Part No. U.S. 89021184, System in Canada 89021186). Automatic DEXRON®-VI Automatic Transmission Transmission Fluid. Usage • To check the PARK (P) mechanism's holding ability: With the engine running, shift to PARK (P). Then release the parking brake followed by the regular brake. Contact your dealer/retailer if service is required. Underbody Flushing Service At least every spring, use plain water to flush any corrosive materials from the underbody. Take care to clean thoroughly any areas where mud and other debris can collect. 6-12