What Causes the Squeaking Sound When Lightly Pressing the Brakes?

[OFrank]

When a squeaking sound occurs while lightly pressing the brakes, it is generally caused by metal hard spots on the surface of the brake pads rubbing against the brake disc. This does not adversely affect the braking performance and can be used with confidence. After prolonged parking, especially in humid weather or after rain, some rust or dirt may form on the brake disc or brake pads. This issue can usually be resolved by driving for a while longer, or by applying butter or specialized lubricating oil at the connection point between the brake pad and the brake caliper. Additional Information: 1. New Car Break-in Period: During the break-in period of a new car, the brakes may produce noise as the brake pads and discs undergo a wear-in process. The noise typically disappears after some driving. 2. Foreign Objects Between Brake Pads and Disc: Sand or other foreign objects may occasionally get lodged between the brake pads and disc, causing noise when braking. 3. Brake Pad-Induced Noise: Brake pads are made from a mixture of materials such as graphite, resin, and iron powder. When the surface of the brake pad encounters raised metal particles, it can produce noise during braking.