Brake pads: when to replace them (signs, mileage and discs)
Updated · Autofy
Brake pads: when to replace them (signs, mileage and discs)
Brake pads are replaced by wear, not by calendar: usually between 20,000 and 60,000 km, sometimes more, depending on driving and pad type. The signs that don't lie: a high-pitched squeal when braking (the metal wear indicator), a metallic grinding, a wear warning light, or friction material down to around 2 to 3 mm. Discs are often replaced every other pad change, once they fall below the minimum thickness stamped on them. Always replace both sides of the same axle.
Why there's no fixed mileage
Unlike an oil change, pad wear depends almost entirely on how you drive:
- City driving wears more than open roads: you brake constantly.
- Driving style: anticipating and easing off early saves a lot of brake wear.
- The car's weight and load.
- Pad type: organic, semi-metallic and ceramic pads don't last the same.
- Terrain: mountain descents wear pads fast.
Hence huge differences, from 20,000 km for a city van to over 60,000 km for a car that mostly does motorways. Front pads, which do most of the braking, usually wear out before the rear.
The signs that don't lie
- A high-pitched squeal when braking. Many pads have a small metal tab that touches the disc when the material is nearly gone. It's deliberate.
- A low metallic grinding. The material is gone and metal is eating the disc: act now.
- An amber wear light on cars with wear sensors.
- A pedal that travels further, or brakes that bite less.
- Vibration in the pedal or steering wheel when braking: more likely warped discs.
- The car pulling to one side under braking: uneven wear or a sticking caliper.
- Brake fluid level dropping: pistons extend as pads wear. See the brake warning light.
Checking yourself
Through the wheel spokes you can often see the pad against the disc. If the friction material looks thinner than about 3 mm, it's time. Look at the disc too: a pronounced lip on its outer edge signals advanced wear.
And the discs?
Discs wear too, more slowly. Their minimum thickness is stamped on the edge or hub. In practice they're often replaced every other time with the pads, or sooner if warped or scored. New pads on worn discs brake less well and wear faster.
Two rules: always replace both sides of the same axle, and bed them in over a few hundred kilometres, avoiding hard stops.
Track wear without thinking about it
Autofy tracks your brakes with a gauge based on the distance since the last change, and accounts for the pad type you fitted (organic, metallic or ceramic). The fluid has its own schedule: see when to change brake fluid.