What Causes Rear Brake Pad Noise?
2 Answers
Rear brake pad noise can be caused by: 1. Break-in period of brake discs and pads producing noise; 2. Metal hard spots generating noise; 3. Severe wear causing warning shims to emit sharp noise as replacement reminder; 4. Foreign objects between brake pads and discs; 5. Improper installation; 6. Poor return of brake caliper pistons. Brake pads (also called brake linings) refer to the friction materials fixed on rotating brake drums or discs. The friction linings and blocks withstand external pressure to create friction, thereby achieving vehicle deceleration. Automotive brake pads consist of steel plates, bonded heat insulation layers, and friction blocks. The steel plates undergo coating treatment for rust prevention.
I've been driving for over twenty years and have often encountered squeaky rear brake pads. The most common cause is excessive wear on the brake pads, exposing the metal parts that then rub against the brake disc, producing a screeching sound. Or, after parking in the rain, the brake discs rust, causing a creaking noise when starting off, which usually goes away after driving for a while. However, a worse scenario is foreign objects like small stones or dust getting stuck between the brake pads, requiring cleaning. Installation issues shouldn't be overlooked either—some shops forget to apply anti-squeal lubricant, causing noise as soon as the pads move. I recommend checking the brake pad thickness during every service; if it's below 3mm, replace them immediately. Don't tough it out, as it affects braking distance and driving safety. I've tried lightly pressing the brakes a few times to clear debris, but for a lasting solution, it's best to visit a professional shop. Otherwise, the wear worsens and could even damage the brake discs, leading to costlier repairs.
