1998 GMC Sonoma Owner's Manual - Page 283

Brake Wear If you have four-wheel drive, your vehicle has four-wheel disc brakes. If not, your vehicle has front disc brakes and rear drum brakes. Disc brake pads have built-in wear indicators that makea 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). Some driving conditions or climates may cause a brake squeal when the brakes are first applied or lightly applied. This doesnot mean something is wrong with your brakes. Properly torqued wheel nuts are necessary to help prevent brake pulsation. When tires are rotated, inspect brake pads for wear and evenly torque wheel nuts in the proper sequence to GM specifications. The brake wear warning sound means that soon your brakes won't work well. Thatcould lead to an accident. When you hear the brake wear warning sound, have your vehicle serviced. If you have rear drum brakes, they don't have wear indicators, but if you ever hear a rear brake rubbing noise, have the rear brake linings inspected immediately. Also, the rear brake drums should be removed and inspected each time the tires are removed for rotation or changing. When you have the front brake pads replaced, have the rear brakes inspected, too. Brake linings shouldalways be replaced as complete axle sets. See "Brake System Inspection" in Section 7 of this manual under Part C "Periodic Maintenance Inspections." NOTICE: Continuing to drive with worn-out brake pads could result in costly brake repair. 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 of brake trouble. 6-33