Peterbilt Medium Duty Truck Owner's Manual - Peterbilt Motors

STARTING AND OPERATING THE VEHICLE
While traveling down steep hills, gravity will tend to
speed you up. You must go slow enough that your
brakes can hold you back without getting too hot. If
you ride the brake pedal and the brakes get too hot,
they may “fade”, causing you to press even harder in
an attempt to maintain your desired stopping power.
The brakes may even fade so much that you won’t be
able to slow down or stop at all.
Using lower transmission gears will help keep the
vehicle from going too fast. Using lower gears allows
engine compression and friction to help slow the vehicle.
Be sure to be in the right gear before you start
down a hill, especially if you have a manual transmission.
You could get hung up in NEUTRAL and lose the
benefit of engine braking. “Coasting” is illegal, and
also VERY dangerous.
Anti-Lock Braking System
This vehicle is equipped with an Anti-Lock Braking System
(ABS). ABS reduces the likelihood of a wheel locking.
If a wheel is about to lock during braking, the ABS will
USING THE BRAKE SYSTEM
automatically adjust hydraulic pressure to the brake calipers
on the appropriate wheel(s) to prevent wheel lock-up.
The ABS is automatically activated when the ignition
switch is turned on.
CAUTION: The center pin of the 7-way trailer
light line may be constantly powered for ABS.
Make sure it will not accidently turn on trailer
equipment.
ABS Warning Lamp
The ABS warning lamp will come on briefly, then go off,
when the key switch is first turned on. If the lamp remains
ON until a speed of 4 mph (6 km/h) is reached, then goes
OFF, there may be a stored fault code. If the lamp
remains ON when a speed in excess of 4 mph (6 km/h) is
reached, there may be an active fault in the ABS system.
CAUTION: If the ABS warning light does not
illuminate when the ignition is first turned on,
there is a problem with the bulb or wiring. You
should have this checked as soon as possible.
Medium Duty (R05/09) Y53-6027 – 125 –