2003 GMC Sonoma Owner's Manual - Page 309

Brake Adjustment Every time you make a brake stop, your disc brakes adjust for wear. If you don't have four-wheel drive and your brake pedal goes down farther than normal, your rear drum brakes may need adjustment. Adjust them by backing up and firmly applying the brakes a few times. Battery Your new vehicle comes with a maintenance free ACDelco@battery. When it's time for a new battery, get one that has the replacement number shown on the original battery's label. We recommend an ACDelco@ battery. See Engine Compartment Overview on page 5- 12 for battery location. Warning: Battery posts, terminals and related accessories contain lead and lead compounds, chemicals known to the State of California to cause cancer and reproductive harm. Wash hands after handling. 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. Your vehicle was designed and tested with top-quality GM brake parts. When you replace parts of your braking system - for example, when your brake linings wear down and you need new ones put in - be sure you get new approved GM replacement parts. If you don't, your brakes may no longer work properly. For example, if someone puts in brake linings that are wrong for your vehicle, the balance between your front and rear brakes can change - for the worse. The braking performance you've come to expect can change in many other ways if someone puts in the wrong replacement brake parts. 5-46