Peterbilt 325 2017, Operator'S Manual, Page: 179 / 392

OPERATING THE BRAKE SYSTEM
Overheated Brakes
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
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 acci-
dently 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.
(03/17) Y53-6060-1C1
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