What Causes the Squeaking Noise When Releasing the Brake During Startup?
3 Answers
Here are the reasons for the squeaking noise when releasing the brake during startup: 1. Releasing the brake too slowly when starting. When you gradually release the brake pedal, the engine already has sufficient power to drive the car forward, but the brake hasn't been fully released yet. As a result, the moving wheels are restrained by the brake system, naturally causing a squeaking noise. 2. The brake disc and brake pads are stuck together due to rust, causing the noise. This situation usually occurs after driving in rainy weather and then leaving the car unused for several days. The brake disc and pads rust and stick together, leading to noise when starting the car again. 3. The semi-metallic material of the brake pads. Brake pads contain a large amount of metal fibers, which sometimes form metal particles. These particles can produce a harsh noise when pressing or releasing the brakes. Typically, this noise disappears after driving for a while. If it persists, it may indicate poor manufacturing quality, and it's advisable to replace the brake pads promptly to avoid damaging the brake disc.
Starting the car with a squeaky brake release – I've encountered this several times over years of driving, mostly minor issues so don't worry too much. The most common cause is worn-out brake pads getting too thin; after much driving, that metallic grinding noise appears. Or during rainy days with high humidity, brake discs rust overnight, producing a creaking sound when releasing the brake in the morning. Another possibility is small sand particles or dust stuck in the brake caliper. If you hear the noise, don't panic immediately – drive for a minute or two and pump the brakes a few times. If the sound disappears, it's fine; if it persists, I recommend heading to a service point promptly. From experience, I once ignored it and ended up with stiff brakes, nearly causing a rear-end collision. So regular brake checks are crucial, especially for those who drive frequently every week – don't skip maintenance to prevent accidents.
From the perspective of vehicle condition, abnormal noises often indicate issues with the brake system that require attention. It could be severely worn brake pads with thickness below the standard, or rust and debris adhering to the brake disc surface, causing friction sounds when releasing pressure. I recommend first identifying the noise type: squeaking usually indicates rust spots, while sharp screeching may suggest excessive wear. A simple solution is to repeatedly press the brakes while stationary to polish the surface. If the noise persists, stop to check the thickness or have a mechanic clean the disc surface. Remember not to ignore this issue, as delayed repairs can worsen wear and damage more components. Regular maintenance like changing brake fluid or inspecting suspension can reduce the risk of abnormal noises. Developing the habit of listening for sounds before driving ensures safety.
