Squealing Noise When Braking
3 Answers
Here are the specific reasons for sharp squealing noises when braking: 1. Improper brake pad installation: When installing new brake pads, the old brake disc was not resurfaced, resulting in a poor fit. A poor fit or installing new pads without resurfacing the old disc causes the new pads to directly rub against the uneven surface of the old disc, leading to uneven wear on the new pads. 2. Brake system malfunction: There may be a defect in the brake system itself, causing the brake pads to only partially contact the brake disc. This increases the pressure per unit area during braking, resulting in abnormal noises. It is recommended to inspect components such as the caliper and guide pins. 3. Presence of foreign objects: Foreign objects cause an uneven contact surface, leading to abnormal noises.
I've encountered the issue of screeching brakes several times, usually indicating the brake pads are nearly worn out or metal parts are grinding. I commute on mountain roads daily, and the brakes squealed every time I applied them. Upon inspection, I found the pad thickness was only 2mm. The metal indicators were scraping against the rotors – that sound is nature's warning not to delay. Worse yet, sometimes small stones or dust get trapped between pads and rotors, amplifying the noise. Last time I ignored this sound, it resulted in rotor damage too, doubling the repair bill. So I've learned my lesson: every 3,000 km I visually check pad condition or monitor sound changes while driving. Safe driving is crucial – if screeching persists, immediately reduce speed and head to a service point without taking risks, especially since wet roads increase accident likelihood. After parking, routinely check wheel hubs for metal dust – early pad replacement saves both hassle and money.
The screeching brake noise reminds me of my neighbor's shared experience, which could stem from three main causes: First, the brake pads are worn too thin, exposing the metal layer that causes friction; second, rust forms on the rotors after rain or prolonged parking, leading to squeaking when the pads make contact; third, foreign objects like sand have entered the system. Even new brake pads may produce slight noise after installation, but this usually disappears within a few weeks. I recommend checking the pad thickness promptly—if it's below 4mm, consider replacing them. Delaying could damage the rotors or even the entire brake caliper. For prevention, avoiding gravel roads and sudden braking can extend pad lifespan. Cleaning the wheel hubs during each car wash is highly effective, and safely removing small stones with a screwdriver yourself is much better. In short, don't wait for the noise to persist—have a professional take a look for peace of mind. Regular brake system maintenance saves money and ensures safety.