Peterbilt 325 2017, Operator'S Manual, Page: 173 / 392

OPERATING THE BRAKE SYSTEM
drive wheel brakes or reducing engine
torque. Engine torque or vehicle
speed should be reduced to eliminate
wheel spin and prevent excessive
application of the ATC system. Except
for checking for proper illumination of
the ABS and traction control warning
lamps when first starting the vehicle,
and for monitoring these lamps
while driving, no special operating
procedures are required. For detailed
system description, see literature for
your specific ABS that was provided
with your vehicle.
This feature helps improve traction
when vehicles are on slippery surfaces
or surfaces with poor traction (i.e.
mud or snow) by reducing drive wheel
overspin. Automatic traction control
works in two different ways:
•
If a drive wheel starts to spin,
ATC applies air pressure to brake
the wheel. This transfers engine
torque to the wheels with better
traction.
•
If all drive wheels spin, ATC
reduces engine torque to provide
improved traction.
ATC turns itself on and off, you do
not have to select this feature. If
drive wheels spin during acceleration,
the ATC Warning Lamp comes on,
indicating wheel spin control is active.
Do not allow the ATC Warning Lamp
to remain on continuously for an
extended length of time. Extended,
continuous use of the ATC can cause
overheating of the drive wheel brakes.
Deep Snow and Mud Switch (option)
A deep snow and mud switch is
included with Wheel Spin Control. The
Deep Snow and Mud feature is helpful
during acceleration. This function
increases available traction on extra
soft surfaces like snow, mud or gravel,
by slightly increasing the permissible
wheel spin. When this function is in
use, the ATC Warning Lamp blinks
continuously.
Off-Road ABS Function Switch
(option)
Your vehicle may be equipped with
a separate switch to activate an
Off-Road ABS function. This function
is NOT to be used for On-Highway
driving but is intended to be used
to improve stopping performance in
Off-Highway conditions (e.g. loose
gravel and mud). The Off-Road ABS
function is accomplished by allowing a
"wedge" of material to build-up in front
of momentarily locked wheels.
Features and Benefits
•
Changes the ABS control limits to
allow for a more aggressive ABS
function while off-road.
(03/17) Y53-6060-1C1
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