Your brakes are your vehicle's most critical safety system. Knowing the warning signs of worn brakes — and understanding the replacement interval — keeps you and others safe.
Brake pad life varies enormously based on driving style, vehicle weight, and pad compound. City driving with frequent stops wears pads much faster than highway driving. Front pads typically last 25,000–65,000 miles; rear pads often last longer since they carry less of the braking load. Performance brake compounds may last shorter; OEM compound pads tend to be durable and quiet.
Key warning signs: squealing or squeaking when braking (many pads have built-in wear indicators that squeal when pads are low), grinding noise (metal-on-metal contact — pads are fully worn and rotors are being damaged), pulling to one side when braking (stuck caliper or uneven pad wear), vibration or pulsation through the brake pedal (warped rotors), and a soft or spongy brake pedal (possible air in the brake fluid or a hydraulic problem).
Brake pad thickness is measured in millimeters. New pads are typically 10–12mm. Most manufacturers recommend replacement at 3–4mm; at 2mm they are critically worn. A brake inspection involves removing the wheel to measure remaining pad thickness, as well as measuring rotor thickness and checking for scoring, cracking, or warping.
Brake rotors can be resurfaced (machined on a lathe) if they have sufficient thickness remaining and no deep scoring or cracks. However, resurfacing reduces rotor mass (heat capacity) and is only cost-effective if the rotor isn't already near its minimum thickness specification. Many mechanics recommend replacing rotors when changing pads for optimal performance and to avoid a second labor charge shortly after.
