Brake Roughness or Chatter Diagnosis

The most common cause of brake chatter on disc brakes is a variation in disc thickness. If roughness, vibration, or pedal pulsation is experienced the disc may have excessive thickness variation. Check rotor parallelism (thickness variation), refer to DISC BRAKE SERVICE.

Excessive lateral runout of the braking disc may cause a "knocking back" of the caliper pistons, possibly creating increased pedal travel and vibration when brakes are applied. Before checking runout, if applicable ensure wheel bearings are adjusted properly.