Fig. 29: Identifying SST In Caliper
Courtesy of MAZDA MOTORS CORP.
REAR BRAKE (DISC) INSPECTION
BRAKE JUDDER REPAIR HINT
Description
Brake judder concern has the following three characteristics:
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.
2008 Mazda CX-9 Grand Touring
2008 BRAKES Conventional Brake System - Mazda CX-9
Microsoft
Sunday, November 15, 2009 9:48:49 AM
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© 2005 Mitchell Repair Information Company, LLC.