What Causes Friction Noise When Not Pressing the Brake?
3 Answers
Friction noise when not pressing the brake could be caused by stiffness between the brake disc and brake pads, which can be resolved by adjusting at a repair shop. The noise may also be related to the hardness of the brake pads, primarily due to excessively hard friction material in the pads. This can be addressed by sanding the brake pads with coarse sandpaper. More details are as follows: 1. Apart from potential issues with the brake pads, the brake disc should also be inspected. Foreign objects between the pad and disc, or grooves on the brake disc causing localized friction, can also lead to abnormal noise, though such brake noise is usually intermittent. 2. Another more serious situation could be significant wear on the brake pads or brake disc, which should be replaced promptly to avoid severe consequences. Brake pads should generally be replaced when their thickness falls below 2mm. 3. Additionally, during rainy or snowy weather, when braking over speed bumps, or during emergency braking, a rhythmic "clicking" noise resembling gunfire may occur, accompanied by strong vibrations in the brake pedal. This indicates that the vehicle's ABS (Anti-lock Braking System) has been triggered, causing the brake noise. In such cases, there is no need for concern, and normal driving can continue.
I've been driving for quite a few years and have encountered the issue of friction noises without pressing the brakes several times. In most cases, this is related to the braking system, such as brake pads sticking to the brake discs, especially common after the brake discs rust during the rainy season. The last time I heard this screeching noise in the garage, I spent quite some time figuring out that it was caused by the brake caliper not fully retracting, leading to friction wear. Additionally, worn wheel bearings can also produce noises when turning, and if severe, it can even affect steering. I usually make it a habit to check for any loose wheels or foreign objects stuck after parking. If the noise persists, don't ignore it; get it checked at a professional shop immediately to prevent it from developing into a dangerous situation like brake failure. Regular maintenance is crucial—cleaning dust and grease from the brake calipers can prevent a lot of trouble.
As a car enthusiast, I always enjoy checking my car for minor issues myself. If there's a friction sound without pressing the brakes, it could be due to severe rust on the brake discs rubbing against components, or the brake return spring aging and causing sticking. Worn wheel bearings are also a common cause, with the sound changing with speed like a whine. I often use a jack to lift the car and manually rotate the tires to check for resistance as a preliminary diagnosis. If a bearing is bad, replacing a new one can cost a few hundred bucks; brake system issues are more troublesome, and delaying repairs can increase tire wear—safety first, after all. I recommend keeping a tire pressure gauge handy to check tire pressure regularly, as unusual noises often warn of mechanical issues that shouldn't be ignored. Don't skimp on cheap, low-quality parts for repairs—it's not worth the risk.
