What Causes Brake Noise at Low Speeds?

[LolaDella]

There are several main reasons why brakes may produce abnormal noises during low-speed driving: 1. Brake pad break-in: New cars or newly replaced brake pads require a break-in period for optimal performance. 2. Foreign particles: Sometimes small particles like sand can get between the brake pads and rotors, causing noise due to friction. This usually doesn't require repair - driving for a while can help dislodge these particles. 3. Brake system malfunction: If the noise is accompanied by brake failure, immediate inspection and repair are needed. Missing or damaged brake rotor mounting screws, or insufficient lubrication can also cause brake noise.

[FelicityLynn]

I've encountered the issue of low-speed brake squealing too many times. The most common causes are metal hard spots or small stones stuck in the brake pads, which create a squeaking sound when braking. Rust on brake rotors also frequently causes this, especially after parking for several days in rainy weather - the friction against the rust layer produces noise. Newly replaced brake pads require a break-in period of about 200 kilometers, during which some squeaking is normal. If the abnormal noise persists for several weeks, it's necessary to check the brake pad thickness - if worn down below 3mm, they must be replaced immediately, otherwise the metal backing plate will directly grind against the rotor, which is dangerous. Lack of lubrication in the brake caliper slide pins can also cause squealing, requiring professional disassembly for inspection. There's also a less common possibility - if the wheel hub bearing is damaged, the wheel vibration during braking can produce noise.

[SawyerLynn]

That squeaking noise when braking at low speeds is really annoying. I usually check the brake pad thickness first; if it's too thin, the metal backing plate rubbing against the rotor can cause that high-pitched sound. If the brake rotor is rusty or contaminated with oil, a thorough cleaning should fix it. Harder brake pad materials last longer but are noisier—switching to ceramic pads makes a big difference. Sometimes, a loose retaining clip causes a clunking sound when braking. Don't overlook the caliper guide pins—lack of lubrication can make them stick, causing uneven pad contact and noise. Rainy days often trigger squeaking because water gets into the rotors, but it usually goes away after a few stops. If new brake pads still squeal, improper installation might require readjustment.

[AlejandroMarie]

I find that low-speed brake squealing is often caused by minor issues. The most typical case is sand getting stuck between the brake pads and rotors, which usually goes away after grinding for a couple of days. When brake pads wear down to their limit, the warning shim will produce a scraping sound as a reminder to replace them. Cold weather can make rubber components stiff, causing squeaks from anti-noise shims, which is normal. Aftermarket brake pads might have material mismatches with the original rotors, but they usually quiet down after a week of re-bedding. Loose wheel lug nuts can also transmit noise to the braking system. If a car sits unused for long periods, friction from the oxidized layer on the rotor surface may cause noise, but it disappears after a few braking applications. Of course, warped rotors or loose wheel bearings require immediate repair.

[Alejandro]

Low-speed brake noise can be categorized into high-pitched squealing and low-pitched metal scraping sounds. A squealing noise is most likely due to brake pads reaching their wear limit, while a dull clunking sound may indicate a stuck caliper. Noise is especially common after car washes due to water retention on the brake rotors. A few hard stops can help remove rust and eliminate noise. Some vehicles naturally have softer brake rotors, which develop grooves over years of use—resurfacing or replacement is necessary. Missing anti-noise paste on the brake pad backing plate can also cause resonant noise. Insufficient lubrication of guide pins is even more critical, as it leads to brake drag, increased fuel consumption, and safety risks. Always check for corroded or chipped edges on brake pads, as these can also be a source of noise.