Brake judder is the phenomenon where with medium to heavy braking from high speed, severe vibration is felt throughout the whole vehicle. It is often attributed to a mode of vibration in which the front suspension executes a predominantly fore and aft vibration with the two road wheels in-phase with each other. Excitation is often provided by the oscillatory forcing generated when applying the brakes to a brake disk that has disk thickness variation.
The driver will experience:
- a regular pulsing of the brake pedal
- a side to side vibration of the steering wheel
- a car body vibration.
Disc thickness variation can be caused by:
- Disc fitment errors
- Driver error or abuse
- Manufacturing fault.