2011 Chevrolet Impala Owner's Manual - Page 283

Vehicle Care Some driving conditions or climates can cause a brake squeal when the brakes are first applied or lightly applied. This does not mean something is wrong with the brakes. Properly torqued wheel nuts are necessary to help prevent brake pulsation. When tires are rotated, inspect brake pads for wear and evenly tighten wheel nuts in the proper sequence to torque specifications in Capacities and Specifications on page 12‑2. Brake linings should always be replaced as complete axle sets. 10-27 Brake Adjustment Every time the brakes are applied, with or without the vehicle moving, the brakes adjust for wear. Brake Fluid Replacing Brake System Parts The braking system on a vehicle is complex. Its many parts have to be of top quality and work well together if the vehicle is to have really good braking. The vehicle was designed and tested with top-quality brake parts. When parts of the braking system are replaced, be sure to get new, approved replacement parts. If this is not done, the brakes might not work properly. For example, installing disc brake pads that are wrong for the vehicle, can change the balance between the front and rear brakes - for the worse. The braking performance expected can change in many other ways if the wrong replacement brake parts are installed. The brake master cylinder reservoir is filled with DOT 3 brake fluid as indicated on the reservoir cap. See Engine Compartment Overview on page 10‑6 for the location of the reservoir. There are only two reasons why the brake fluid level in the reservoir might go down: . Brake Pedal Travel See your dealer if the brake pedal does not return to normal height, or if there is a rapid increase in pedal travel. This could be a sign that brake service might be required. The brake fluid level goes down because of normal brake lining wear. When new linings are installed, the fluid level goes back up. A fluid leak in the brake hydraulic system can also cause a low fluid level. Have the brake hydraulic system fixed, since a leak means that sooner or later the brakes will not work well. .