2003 GMC Envoy Owner's Manual - Page 334

Checking Brake YOU Fluid can check the brake fluid without taking off the cap. Always clean the brake fluid reservoir cap and the area around the cap before removing it. This will help keep dirt from entering the reservoir. I I 1 With the wrong kind fluid in your brake of system, your brakes may not work well, or they may not even work all. This could cause a at crash. Always use the proper brake fluid. Notice: Using the wrong fluid can badly damage brake system parts. For example, just a few drops o f mineral-based oil, such as engine oil, your in brake system can damage brake system parts so badly that they'll have to be replaced. Don't let someone put in the wrong kind of fluid. If you spill brake fluid on your vehicle's painted surfaces, the paint finish can be damaged. Be careful not to spill brake fluid on your vehicle. If you do, wash it off immediately. See "Appearance Care" in the Index. After work is done on the brake hydraulic system, make sure the level is above the MIN but not over the MAX mark. What to Add When you do need brake fluid, use only DOT-3 brake fluid. Use new brake fluid from a sealed container only. See Part D: Recommended Fluids and Lubricants on page 6-17. 5-39