What Causes Brake Noise?
2 Answers
Reasons for brake noise: If it's a new car, since both the brake pads and brake discs are new and still in the break-in period, they may produce a slight hissing sound. This is normal and usually disappears on its own after a few hundred kilometers. Foreign objects between the brake pads and brake discs, such as sand or small stones entering the gap due to strong winds, can also cause a hissing sound. A vibrating or humming noise when braking in reverse is generally due to changes in the friction pattern. Normally, braking occurs while moving forward, so reversing can cause misalignment in the friction pattern, leading to noise. This typically occurs at low speeds and is usually absent at high speeds. It is also normal and can be resolved after a few more friction cycles. In winter, prolonged exposure to cold can cause ice to form at the contact points between the brake pads and brake discs. A slight noise may occur when starting the car as the ice melts, which is also a normal phenomenon.
I've been driving for eighteen years, and brake squealing is a common occurrence. The most frequent cause is brake pads worn too thin, where the metal part directly scrapes against the brake disc, producing that sharp, screeching sound—especially noticeable during sudden braking. After rain or in humid weather, the surface of the brake disc rusts, causing a squeak when you first apply the brakes, though it usually disappears after a car wash or a short drive. Newly replaced brake pads may also have a break-in period, with some noise in the first few days being normal, but if it persists too long, it’s a cause for concern. Small stones getting lodged between the brake disc gaps are another common culprit, and removing them yourself usually solves the issue. Though minor, squealing can hint at bigger problems, like insufficient lubrication or a stuck piston. I recommend getting it checked promptly at a reputable repair shop—don’t take risks on the road; safety comes first. During regular maintenance, have a mechanic check the brake pad thickness to prevent accidents.
