Первый, listen to the sound. When stepping on the brake, if you hear a “creaking” or metal grinding sound, it indicates that the brake pads have worn to the limit and are starting to rub against the brake disc. В этот момент, it is necessary to replace them immediately.
Second, check the thickness. The new brake pads are quite thick, but if they are worn down to less than five millimeters, it’s time to replace them.
Third, rely on your foot feel. When stepping on the brake, if you feel that the brake becomes soft and you have to step deeper to stop, and you notice the car deviates from a straight line when braking, this is a sign that the brake pads are getting thinner.