Why is there a noise when releasing the brake?

[LaCora]

This is a normal phenomenon for automatic transmission vehicles. The brake noise is caused by the gap between the brake pads and the uneven hardness of the brake discs, which contain materials like copper or other metals, leading to an uneven surface on the brake pads. The details are as follows: 1. The lighter and slower, the more noticeable: The slower and lighter you release the brake, the more noticeable this noise becomes. This is because in an automatic transmission vehicle, as long as the gear lever is not in Park (P) or Neutral (N), the engine continues to output power, even at idle. To stop the vehicle, you must press the brake pedal. 2. Braking force versus power: When starting, the engine's power is already applied to the wheels, but the wheels do not move because the braking force is greater than the power. When the braking force is less than the power, the wheels start to move. As you release the brake pedal, when the power and braking force reach a critical point, the friction between the brake pads and discs produces noise. If you quickly release the brake pedal (when conditions permit), there is no noise.

[VonOmar]

Brake lift noise can be caused by several common issues, which I've encountered over years of driving. The most frequent cause is worn brake pads or small stones stuck in them, producing a squeaking sound. Alternatively, rust or water on the brake disc surface can create friction noise. Loose caliper components may also cause creaking, especially in humid weather. Another possible reason is related to the suspension system, such as worn steering knuckles, which can produce abnormal vibration sounds when lifting the foot. If the noise only occurs under specific conditions, like during cold starts, it's likely temporary and can be alleviated by pressing the brakes a few more times. However, if the noise persists or worsens, it's advisable not to ignore it and to promptly visit a reliable repair shop to check brake pad thickness and overall system safety. Regular maintenance, such as biannual brake inspections, can significantly reduce such issues and ensure smooth driving. I usually practice gentle brake lifting to extend component lifespan, which works well. In summary, while brake noise may seem minor, timely attention ensures peace of mind.

[EmersynMarie]

A squeaking noise when releasing the brake pedal is commonly seen in aging brake systems. From my research, this could be due to uneven friction from brake pad material or foreign contaminants, like the scraping sound of adhered dirt. Warped brake rotors or rust spots can also cause clunking sounds upon release. Sticky caliper movement or aged springs may lead to component collisions creating noise. Worn suspension bushings can indirectly contribute, producing creaks during pedal release. Don't panic when this happens—first inspect your brake pads yourself; replace them if excessively worn. Humidity increases occurrence, so park in dry conditions when possible. For maintenance, simple brake component cleaning can eliminate temporary noises. I prefer applying regular rotor protective coatings to minimize rust. Adopt gentle driving habits—avoid abrupt braking—to safely extend system lifespan. If squeaking persists with brake softness, seek immediate repair for safety.

[DiAdelyn]

Brake squealing is often caused by worn brake pads. I've seen many cases where rusted brake discs or foreign objects rubbing against them produce a squeaking sound. Loose calipers can also create a clicking noise, which tends to worsen in humid weather. A simple test is to pump the brakes a few times and observe any changes. Ignoring these issues may affect braking performance and pose safety risks. It's recommended to promptly inspect the brake system and suspension components for proper condition.

[DeEliana]

A squeaking noise when releasing the brake pedal usually originates from brake pads or rotors. Having dealt with similar cases, common causes include foreign objects like small stones scraping against the rotor, producing sharp noises. Surface rust on brake rotors can also cause squeaking, especially noticeable after rain. Abnormal movement in caliper components may generate vibration sounds. Worn suspension bushings can indirectly lead to knocking noises. For this issue, start with simple self-checks: replace brake pads if they're worn thin. Regular cleaning of the braking system during maintenance can prevent such problems. I also recommend checking wheel alignment, as improper tire wear can exacerbate noise issues. If the sound intensifies or braking performance deteriorates, stop immediately and seek professional technicians to inspect electrical circuits and mechanical safety. Developing gentle driving habits effectively reduces wear risks.