Friction material deposits are a common cause of steering wheel vibration when braking. this form of brake shudder is the result of intermittent grabbing and releasing of the brake pads on the disc rotor surface. Brake shudder due to friction material deposits is frequently mistaken for disc thickness variation (DTV) or the common industry term warped discs.
Friction material transfer is related to the organic elements component of the brake pad material. While an evenly deposited friction material transfer layer is a critical component of modern braking mechanics, it is when this player becomes irregular in thickness that problems occur. The irregular thickness of material deposits causes alternating, amplified torque application will cause the steering wheel to vibrate back and forth, sometimes violently in extreme cases.
How does this occur?
The most common cause of irregular friction material deposits is poor selection of the friction material and disc rotor combination for the intended application. All friction materials have a maximum operating temperature. When this temperature is exceeded, the material may begin to break down and release large deposits rather than the typical fine dust generated by braking friction.
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