OPERATOR'S MANUAL

USING THE BRAKE SYSTEM STARTING AND OPERATING THE VEHICLE
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Medium Duty (R05/09)
WARNING! No indication will be given via the
dashboard warning lights or buzzer if tires of
the wrong size are installed on your vehicle.
The Anti-Lock Brake System (ABS) is cali-
brated for the specific tire revolutions per
mile. Use of a tire and/or wheel size different
from that originally installed on your vehicle
may cause the ABS system to not function
during a hard braking event. This could cause
an accident, resulting in death or personal
injury. Consult with your Peterbilt dealer
before using a different tire and/or wheel size
than was originally installed on your vehicle.
Parking Brake Burnishing
WARNING! If a new drum or new brake shoes
are installed, the driveline brake must be bur-
nished. Failure to properly burnish the park-
ing brake before putting it in service could
result in an inoperative parking brake, possi-
ble vehicle rollaway, and death, personal
injury or damage to the vehicle.
This procedure is recommended for new vehicles where
less lever actuation force is required. This procedure is
mandatory whenever the driveline brake shoes or brake
drum are replaced.
1. Drive the vehicle at 15 mph (24 km/h) in a low gear
(first or second) on a dry, hard road surface.
2. Apply the parking brake lever with a moderate force
(approximately 40 pounds) until the vehicle is
brought to a stop. Do not allow the wheels to lock up.
3. After stopping, release the parking brake lever and
drive the vehicle at 20 mph (32 km/h) in a low gear
for approximately 2.5 miles, to allow the brake drum
to cool.
4. Repeat steps 1, 2, and 3 above until a total of 10
stops have been completed.
5. Adjust the parking brake lever. See the Medium Duty
Maintenance Manual.