What indicates that brake pads need replacement?

The indication that brake pads need replacement is often marked by a squeaking or grinding noise while braking. This phenomenon occurs because many modern brake pads are designed with wear indicators that create a noise when the pads become too thin. Squeaking typically arises from the metal shim that comes into contact with the rotor when the pads wear down significantly, signaling that the pads have reached a minimum thickness. If brake pads wear down to the point where metal is exposed, grinding noises can occur, indicating severe wear and necessitating immediate replacement to prevent damage to the rotors.

While a firm brake pedal touch is a sign of an effective braking system and may suggest that the hydraulic system is functioning well, it does not specifically indicate a need for brake pad replacement. Similarly, a warning light on the dashboard could signal various issues, but it doesn't exclusively point to pad wear. An increase in fuel consumption is generally unrelated to brake pad condition. Thus, the audible signs of wear, such as squeaking or grinding, are the most direct indicators that brake pads require attention.