What Causes Brake Pad Noise at Low Speeds?
4 Answers
Brake pads squeaking at low speeds may be due to brake pad malfunction, improper bedding-in of the brake pads, or misalignment of the brake pads. This situation requires timely repair. Detailed explanations are as follows: 1. Bedding-in period: The brake pads and rotors used in cars require a certain period of bedding-in. If newly replaced brake pads are producing noise, it might be caused by poor bedding-in between the brake pads and rotors. When braking, the noise occurs simultaneously. 2. Service life: Brake pads are consumable items that need replacement after certain usage. This depends on the vehicle's usage conditions. Generally, during normal vehicle operation, front brake pads wear faster than rear ones. The service life of front brake pads is approximately 30,000-50,000 kilometers, while rear brake pads last about 100,000-150,000 kilometers.
It's quite common to hear squeaking sounds when braking at low speeds. I was puzzled when I encountered it myself last time. It could be that the brake pads are worn to their limit, and the metal wear indicator is scraping against the brake disc, causing a screech. Alternatively, the brake disc surface might be rusted or grooved, especially noticeable after parking for a few days in rainy weather. If you've just replaced the brake pads, they might not be properly bedded in yet—it could take a few hundred kilometers for the noise to disappear. I recommend checking the brake pad thickness first; if it's less than 3mm, they must be replaced. Don't just opt for cheap ordinary pads—ceramic compound pads can reduce strange noises caused by dust buildup. Remember to rinse the inner side of the wheels when washing your car, as small stones stuck in the brake system can cause this noise. If the noise is accompanied by vibration, check immediately if the brake caliper guide pins are seized.
I've dealt with low-speed brake squealing issues many times. The key is to differentiate the situations: initial cold-start brake squeals are usually harmless as the moisture on rotors dries off; if there's consistent high-pitched noise at low speeds, it's likely due to hardened spots wearing on brake pads. DIY checks first: feel if wheel hubs are noticeably hotter after parking – this may indicate caliper drag from incomplete retraction. Also inspect rotor edges for raised lips – if exceeding 1mm, resurfacing is needed. Last time, my car had metallic debris embedded in cheap pads causing clunking noises at low speeds. For prevention, biannual 20,000km brake maintenance is advisable – cleaning guide pins and applying specialty grease prevents 90% of noises. Avoid aggressive braking, especially after rain.
Don't panic about low-speed brake squealing - after 15 years of driving, I'm used to these minor issues. The most common cause is sand or metal particles stuck in brake pads, creating a clicking sound during low-speed friction. An easy DIY fix: find a safe road section, gently apply brakes several times at 40 km/h - this often grinds away the debris. If the noise persists for 2-3 weeks, pay attention - it's likely the wear indicator tabs are contacting the rotor, signaling pad thickness below 5mm (time for replacement). Remember to inspect brake discs during pad changes - uneven wear causes low-speed braking vibration. Have mechanics measure disc runout with a dial indicator; exceeding 0.05mm requires resurfacing. Regular wheel hub dust cleaning is crucial.
