2007 Cadillac STS Owner's Manual - Page 406

What to Add When you do need brake fluid, DOT-3 brake fluid is recommended for use. DOT-4 brake fluid is also compatible with your vehicle's brake system parts. However, if you choose to use DOT-4 fluid, it is recommended that you flush your brake hydraulic system and refill it with new DOT-4 fluid at a regular maintenance service every two years. See Additional Required Services on page 508. Use new brake fluid from a sealed container only. See Recommended Fluids and Lubricants on page 516. 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. Notice: • Using the wrong fluid can badly damage brake system parts. For example, just a few drops of mineral-based oil, such as engine oil, in the brake system can damage brake system parts so badly that they will have to be replaced. Do not 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 Washing Your Vehicle on page 480. Brake Wear Your vehicle has four-wheel disc brakes. Disc brake pads have built-in wear indicators that make a high-pitched warning sound when the brake pads are worn and new pads are needed. The sound may come and go or be heard all the time your vehicle is moving, except when you are pushing on the brake pedal firmly. {CAUTION: With the wrong kind of fluid in the brake system, the brakes may not work well, or they may not even work at all. This could cause a crash. Always use the proper brake fluid. 406