What Causes Abnormal Noise When Braking a Car?
3 Answers
Here is a detailed introduction to the causes of abnormal noise when braking a car: 1. Break-in noise between brake pads and rotors: Brake pads consist of steel plates, bonded insulation layers, and friction blocks. Newly replaced brake pads may not properly integrate with worn rotors due to differing wear levels, resulting in braking noise. 2. Severe wear of brake rotors and pads: When brake pads wear to their limit, the warning shim contacts the rotor, producing abnormal sounds. Brake pads should be replaced promptly. 3. Brake caliper noise: If brake calipers aren't cleaned regularly, accumulated debris can cause noise.
I've been driving for many years and have encountered brake noise issues quite often. Usually, it's because the brake pads have worn thin, and the metal part comes into contact with the brake disc, producing that sharp screeching sound. It could also be due to sand or dust stuck on the surface of the brake disc, causing a rattling noise while driving. After rain or in humid weather, the brake disc is prone to rust, resulting in a few clicking sounds when starting. Another possibility is insufficient lubrication of the brake caliper or loose components causing vibration noise. If the brake disc is uneven, stepping on the brakes will produce a shaking sensation accompanied by noise. To address this, the first step is to check the thickness of the brake pads—if they're too thin, they need to be replaced. Don’t underestimate these noises; they can affect braking performance. Safety comes first, so it's advisable to get them checked at a professional repair shop as soon as you notice them.
When encountering brake noise issues, I first inspect it myself. The most common cause is severely worn brake pads, where the wear indicator screeches non-stop against the rotor. Sometimes small stones get lodged in the gaps, chirping like little birds. After leaving the car parked for days in rain, rust on brake discs may cause a few squeaks that disappear after driving briefly. Occasionally, OEM brake pad materials tend to squeak at low temperatures. However, persistent abnormal noises may indicate aging brake systems, such as warped rotors or caliper malfunctions. Most cases can be resolved by cleaning foreign objects or replacing pads. I regularly measure brake pad thickness and replace them when excessively thin to maintain smooth braking. Never ignore unusual noises to prevent extended stopping distances and potential accidents on the road.
