What Is an Acceptable Front and Rear Brake Lining Thickness?
An acceptable front or rear brake lining thickness is anywhere between the standard 12 millimeter thickness when the break pads are new and 3 millimeter thickness after they become worn. At 3 millimeters, the sensors get exposed and make contact with the disc or rotor, creating a squealing sound.
When the brake pad linings reach the 3 millimeter thickness, only around 25% of pad life remains. When checking brake pads for wear level, it should be remembered that there are pads both outside and inside the rotors, and so both will need to be checked to get an accurate wear measurement.