User Manual

WARNING
If a new drum or new brake shoes are
installed,
the driveline brake must be
burnished. Failure to properly burnish
the parking brake before putting it in
service could result in an inoperative
parking brake, possible vehicle roll-
away, and serious personal injury or
damage to the vehicle.
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.
ABS W
arning 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 illu-
minate 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.
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 Sys-
tem
(ABS) is calibrated 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 or serious
personal injury. Consult with your deal-
er before using a different tire and/or
wheel size than was originally installed
on your vehicle.
Air Brake System (option)
This vehicle's braking system and many
vehicle accessories may depend on the
storage and application of a high-pressure
air supply. For vehicles equipped with an
air brake system, the service brake,
parking brake, and trailer brake will utilize
this supply.
Vehicles equipped with an air brake system
are of the dual circuit type: it has a circuit
for the front wheels, a separate circuit for
the rear wheels, and one for the trailer. The
system is supplied by an engine-driven
compressor. The vehicle's compressor
DRIVING - Air Brake System (option)
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