One of the more common causes for brake shudder is DTV (Disc Thickness Variation).
In most cases DTV is the result of run out in the disc rotor. The rotor friction surface oscillates in and out causing the brake pad to wear the high points of the disc resulting in a thickness variation around the rotor.
As a result of DTV, the pads will grab and release under braking as the rotor thickness changes around the diameter. This causes a shudder or vibration in the steering wheel and front end of the vehicle. In severe cases the brake pedal will noticeably pulse up and down when pressure is applied.
DBA disc rotors are precision CNC machined to ensure minimal runout during the manufacturing process to tolerances far less than the maximum 0.05mm industry standard. Failure to follow good industry practice of properly cleaning the hub and rotor surfaces is the most common cause for rotor run out resulting in DTV and brake shudder.
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