Why is there a strange noise when braking in reverse?
2 Answers
It is normal to hear strange noises when braking in reverse. Reasons for the noise: Since the vehicle moves forward for 99% of its mileage, the brake pads and discs wear in one direction over time. Brake pads contain certain metal components, which can develop small metal burrs on one side. When braking in reverse, these burrs come into contact with the brake disc, causing the noise. This is a normal phenomenon. Function of brake pads: High-quality brake pads act as protectors for both the driver and the vehicle. The heat insulation layer is made of non-conductive materials to prevent heat transfer. The friction block consists of friction materials and adhesives, which create friction against the brake disc or drum when braking, thereby slowing down or stopping the vehicle. Due to friction, the friction block gradually wears out. Generally, lower-cost brake pads wear out faster.
My old car often squeaks when braking in reverse, and I later found out it's due to rust on the edges of the brake discs. Especially after rainy days, the friction between the brake pads and the rust causes noise. Additionally, when the brake pads wear down to their limit, the metal warning tabs on the back scrape against the brake disc, producing a sharp sound. If you've just replaced the brake pads, there might be a break-in period of a few hundred kilometers, during which reverse braking can easily produce friction noise. Another possibility is that the brake caliper guide pins lack lubrication, preventing the brake pads from fully retracting. Once, I took it apart myself, cleaned the rust, and applied some special grease, which improved the situation significantly. Leaving it untreated for a long time can accelerate brake pad wear, so it's advisable to check the thickness of the brake pads and, if necessary, have a professional mechanic make adjustments.
