What Causes the Squeaking Sound When Braking at Low Speeds?
2 Answers
Car braking at low speeds causes squeaking sound due to: 1. Missing or damaged brake disc fixing screws; 2. Insufficient lubrication in the braking system; 3. Small particles between brake pads and discs; 4. Dirty brake disc surface or uneven material density causing severe wear. Braking, also known as deceleration, refers to the action of stopping or reducing the speed of moving locomotives, vehicles, and other transportation tools or machinery. Its working principle is: fixing a wheel or disc on the machine's high-speed shaft, installing corresponding brake shoes, bands, or discs on the machine base, which generate braking torque under external force.
I've encountered the issue of squeaking brakes during low-speed driving several times, and the most common cause is worn-out brake pads. There's a small metal indicator embedded in the brake pad that scrapes against the rotor when the pad reaches its wear limit, producing a warning sound. If it's just rained or the car hasn't been driven for a while, surface rust on the rotors can also cause this friction noise during low-speed braking. Newly replaced brake pads require a break-in period, and the noise typically disappears after a few hundred kilometers of driving. I've also noticed that some hard-compound brake pads are inherently prone to noise, but this doesn't affect braking performance. Occasionally, small stones trapped between the brake pad and rotor can cause squeaking, but the noise stops once the debris falls out. Regular inspection of brake pad thickness is crucial - they should be replaced when worn down to less than 3mm. If the noise becomes progressively louder or develops into a harsh metallic screeching sound, it's wise to visit a repair shop immediately for inspection.
