Steering Wheel Vibration
Steering wheel vibrates in the direction of its rotation. This characteristic is most noticeable when applying brakes at a vehicle speed of 100-140 km/h {62-87 mph}.
Floor Vibration
When applying brakes, the vehicle body shakes back and forth. The seriousness of shake is not influenced by vehicle speed.
Brake Pedal Vibration
When applying brakes, a pulsating force tries to push the brake pad back. The pulsation is transmitted to the brake pedal.
The following are the main possible causes of brake judder
Due to an excessive runout (side-to-side wobble) of disc plate, the thickness of disc plate is uneven.
If the runout is more than 0.05 mm {0.002 in} at the position 10 mm {0.39 in} from the disc plate edge, uneven wear occurs on the disc plate because of uneven pad/plate contact.
If the runout is less than 0.05 mm {0.002 in} , uneven wear does not occur.
The disc plate is deformed by heat.
Repeated panic braking may raise the temperature in some portions of disc plate by approx. 1,000°C {1,832°F}. This results in deformed disc plate.
Due to corrosion, the thickness and friction coefficient of disc plate change.
If a vehicle is parked under damp conditions for a long time, corrosion occurs on the friction surface of disc plate. The thickness of corrosion is uneven and sometimes appears like a wave pattern, which changes the friction coefficient and causes a reaction force.
Scheme 40
Steering wheel vibrates in the direction of its rotation. This characteristic is most noticeable when applying brakes at a vehicle speed of 100-140 km/h {62-87 mph}.
When applying brakes, the vehicle body shakes back and forth. The seriousness of shake is not influenced by vehicle speed.
When applying brakes, a pulsating force tries to push the brake pad back. The pulsation is transmitted to the brake pedal.
The following are the main possible causes of brake judder
Due to an excessive runout (side-to-side wobble) of disc plate, the thickness of disc plate is uneven.
If the runout is more than 0.05 mm {0.002 in} at the position 10 mm {0.39 in} from the disc plate edge, uneven wear occurs on the disc plate because of uneven pad/plate contact.
If the runout is less than 0.05 mm {0.002 in} , uneven wear does not occur.
The disc plate is deformed by heat.
Repeated panic braking may raise the temperature in some portions of disc plate by approx. 1,000°C {1,832°F}. This results in deformed disc plate.
Due to corrosion, the thickness and friction coefficient of disc plate change.
If a vehicle is parked under damp conditions for a long time, corrosion occurs on the friction surface of disc plate.
The thickness of corrosion is uneven and sometimes appears like a wave pattern, which changes the friction, coefficient and causes a reaction force.
