What Causes the Squeaking Sound When Releasing the Brakes?

[VonCooper]

Here are the reasons for the squeaking sound when releasing the brakes: 1. Noise occurs after replacing the original brake pads with new ones. Since the original pads are factory parts and often do not produce noise even when slightly scratched, 90% of repair shops and drivers do not suspect that the original pads could damage the brake discs. As a result, they often fail to check for scratches on the brake discs when installing new pads. Only after the new pads start making noise do they inspect the discs and discover scratches. This frequently leads to drivers demanding compensation for the brake discs from the repair shops, dealers, or manufacturers who installed the new pads. 2. The brake disc surface is smooth, but the new brake pads produce noise. A sudden noise after driving for a while is mostly caused by hard objects such as sand, gravel, or metal scraps getting caught between the brake pads when braking. This not only causes noise but can also easily damage the discs. 3. Using asbestos-containing brake pads. (Noise occurs even when the brake disc surface is completely smooth and flat.) While semi-metallic asbestos-free brake pads offer longer mileage and are more environmentally friendly and healthier, their material is relatively hard. In contrast, asbestos brake pads are softer, so they often do not produce noise even if the brake discs have scratches, and they provide a gentler braking feel. In this case, the only solution is to replace the pads with new ones.

[Victor]

I have considerable driving experience and have encountered the squeaking sound when releasing the brakes several times. Most of the time, it's due to worn brake pads or dirt on the brake discs, such as dust, mud, or small stones. Especially after rainy or humid weather, the moisture can amplify the friction noise. I used to ignore it, but the sound grew louder and almost affected braking performance. I recommend having a mechanic briefly inspect the brake components during each car wash for timely cleaning or pad replacement. Don’t underestimate this issue—if the brakes fail, it can be extremely dangerous on the highway. Develop a habit of regular maintenance; I personally have my brake system checked at the garage every six months to ensure everything is in order.