What Causes Brake Disc Noise?
2 Answers
Reasons for brake disc noise: 1. Rusty brake calipers: If brake fluid is not replaced for a long time, it will deteriorate, and the moisture in the fluid can cause the calipers to rust, leading to friction and noise. 2. Slow return of the master cylinder: Abnormal return of the brake calipers can also cause brake pad noise. 3. New car break-in period: The brake pads and discs of a new car are in a brand-new state and still in the break-in period, which may produce some noise. This is normal. 4. Foreign objects between the brake pads and discs: While driving, foreign objects like sand or gravel can get lodged between the brake pads and discs, causing noise during braking. 5. Hard brake pad material: Most OEM brake pads are made of semi-metallic materials, which can easily produce noise when rubbing against the brake discs. 6. Improper installation of the brake system: If the spacing between the brake pads and discs or the tightness of the nuts is not properly adjusted during installation, it can cause noise. 7. Noise during reverse braking: Since brakes mostly work during forward motion, prolonged wear in one direction can create burrs on the reverse side. When braking in reverse, these burrs rub against the brake disc, causing noise. Solutions for brake pad noise: For new cars, the noise will stop after the break-in period. For noise caused by foreign objects, the owner can have the brake discs cleaned at a repair shop, as the issue usually lies with the discs rather than the pads. For noise due to improper installation, it's recommended to visit a 4S shop to adjust the spacing and nut tightness. For noise during reverse braking, the brake pads can be removed and polished or replaced.
Recently, I've been driving more frequently and noticed a sharp noise when braking. I immediately went to get it checked, and it turned out the brake pads were worn thin, causing the metal parts to scrape against the brake disc and produce the sound. Scratches on the brake disc can also create noise, especially when new brake pads are installed and need a break-in period—the noise usually diminishes within a few hours. The sound can be more noticeable in rainy or dusty conditions because the brake pads pick up dust particles. Never ignore this noise. Last time I delayed the repair, the brake disc was completely ruined, costing nearly two thousand to replace, and I almost had an accident. I recommend checking your brakes monthly to ensure safe driving—it saves both peace of mind and money.
