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To return to a previously set speed
Instrument panel-mounted
controls:Press RESUME -. For
RESUME - to operate, the vehicle
speed must be above 30 mph (48
km/h) or engine speed must be
above 1,000 RPM.
Steering wheel-mounted
controls:Press RES. For RES to
operate, the vehicle speed must be
above 30 mph (48 km/h).
SET RESUME
RES
SET
ACCEL
COAST
Driver controls
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Backing up
To reduce the risk of the possibility of personal injury while
backing the vehicle, always be sure your vehicle’s path is clear.
Before backing your vehicle, be sure you can do so safely. If anything
behind the cab limits your view, do not rely on mirrors alone to assure
that your intended path is clear. If other people are in the vicinity, have
someone standing well behind your vehicle and outside of your intended
path (visible through an exterior mirror) guide you as you back up.
Although OSHA or some governmental regulations may require the use
of an electrical or mechanical back-up alarm to warn bystanders, such an
alarm does not assure that the intended path is clear. When in doubt, get
out of the vehicle and visually check the intended path is clear; back-up
slowly as to allow others time to move, if necessary.
If an electrical back-up alarm is installed, it should be connected to the
back-up lamp circuit.
Parking your vehicle
Always use the parking brake. When parking on a grade, block the
wheels and turn the front wheels to one side so that if the vehicle rolls,
the front tires will act against the curb to stop the vehicle. The front
wheels will be more effective at stopping a rolling vehicle than the rear
wheels.
When parking your vehicle, do not leave the transmission in
gear; if the key is in the ON position and the vehicle rolls, the
engine could start. Failure to follow these instructions could result in
an unattended vehicle moving, possibly causing personal injury or
property damage.
Driving through water
If driving through deep or standing water is unavoidable, proceed very
slowly especially if the depth is not known. Never drive through water
that is higher than the bottom of the hubs (for trucks) or the bottom of
the wheel rims (for cars). Traction or brake capability may be limited
and your vehicle may stall. Water may also enter your engine’s air intake
and severely damage your engine, drive axles or the transmisison
(through the breather ports).
Once through the water, always dry the brakes by moving your vehicle
slowly while applying light pressure on the brake pedal. Wet brakes do
not stop the vehicle as quickly as dry brakes.
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Parking brake
Apply the parking brake whenever
the vehicle is parked. To set the
parking brake, pull handle up until it
snaps into the locked position.
When the parking brake is out of
adjustment, seek service
immediately.
The parking BRAKE warning lamp
in the instrument cluster illuminates
and remains illuminated (when the
ignition is turned ON) until the
parking brake is released.
Do not use the gearshift selector in place of the parking brake.
Always set the parking brake fully AND make sure the gearshift
selector is in R (Reverse) for vehicles equipped with manual
transmission, P (Park)(if equipped)or N (Neutral) for vehicles with
automatic transmission. Use of wheel chocks is also recommended in
hilly or off-road usage.
Unexpected and possible sudden vehicle movement may occur if
these precautions are not taken.
P
BRAKE
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The parking brake is not recommended to stop a moving vehicle.
However, if the normal brakes fail, the parking brake can be used to stop
your vehicle in an emergency. Since the parking brake only applies
retardation to the rear wheels, the vehicle’s stopping distance will
increase greatly and the handling of your vehicle will be adversely
affected.
Push the palm release lever on the
parking brake handle and push
down as far as possible to release
the brake. Driving with the parking
brake on will cause the brakes to
wear out quickly and reduce fuel
economy.
POWER PARK (AIR-OPERATED PARKING BRAKE) OPTION
(IF EQUIPPED)
This feature uses a brake chamber mounted on the chassis to power a
spring-applied, air-released driveline parking brake. It is controlled by a
yellow, dash-mounted parking brake knob.
Applying the parking brake
To apply the parking brake, pull the yellow, dash-mounted parking brake
knob. A red light on the dash panel should illuminate indicating that the
parking brake has been successfully set.
Note:If the park brake indicator light blinks and a warning chime
sounds when the control knob is pulled, the parking brake is not
functioning properly; seek immediate service from your dealer. Refer to
theParking Brake Warning Systemsection.
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yellow control knob is pulled out again, the light will blink and the chime
will sound as a reminder that immediate service is required to the
parking brake system.
Releasing spring manually
Do not attempt to disassemble the parking brake chamber under
any circumstances. The high spring load may cause serious
injury.
If air pressure is released from the spring brake chamber the power
spring applies the brake and, unless air pressure can be re-established,
the spring brake must be released as follows in order to move the
vehicle.
Block the wheels to help prevent the vehicle from moving.
Unexpected and possibly sudden vehicle movement may occur if
these precautions are not taken.
Loosen the jam nut (1) and un-thread the adjustment rod (2) from the
chamber to reduce tension on the cable (3). Continue to un-thread the
adjustment rod all the way and remove it from the chamber. The nut and
shaft are metric.
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Cam brakes - automatic slack adjusters
Standard air brakes (cam) are
equipped with automatic brake
adjusters. Automatic adjustment
occurs during brake applications.
Inspect brakes for proper
adjustment at the intervals listed in
the vehicle Service Maintenance
Guide.
Emergency air brake
All vehicles are equipped with a dual brake system. In the unlikely event
of a failure of one system, the second system will function for emergency
stopping. These systems are all controlled by the brake pedal in the
same manner as for normal stops.
Do not continue to operate the vehicle with a failure of one of
the systems. Take the vehicle to your dealer for service
immediately.
Parking brake
Do not use the gearshift selector in place of the parking brake;
unexpected and possible sudden vehicle movement may occur if
these precautions are not taken. Always set the parking brake fully
AND make sure the gearshift selector is in R (Reverse) for vehicles
equipped with manual transmission, N (Neutral) for vehicles with
automatic transmission (except Allison 2400 transmission) or P (Park)
(Allison 2400 transmission).
If the service brakes should fail to operate while the vehicle is in motion,
you can make an emergency stop with the parking brake. Since the
parking brake only applies stopping power to the rear wheels, the
vehicle’s stopping distance will greatly increase and the handling of the
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vehicle will be adversely affected. Repairs should be made immediately
to an inoperative air brake system circuit.
Parking brake control (knob)
Pull the yellow parking brake knob
out to apply the parking brake. Push
the knob in to release the parking
brake.
This control is used for
parking only. Do not leave
the vehicle unattended after
setting the parking brake without
placing the transmission in R
(Reverse) for manual
transmission, N (Neutral) for
automatic transmission (except
Allison 2400 transmission) or P
(Park) (Allison 2400
transmission). Use of wheel
chocks is also recommended in
hilly or off-road usage.
The parking BRAKE warning lamp
in the instrument cluster illuminates
and remains illuminated (when the
ignition is turned ON) until the
parking brake is released.
Releasing spring brake with air pressure
The air system in all vehicles with spring-actuated rear wheel parking
brakes is equipped with a tank valve located on the supply or service air
tank for connection to an outside air supply. The valve permits the
system to be recharged with air from an outside source, releasing the
spring-actuated parking brakes. The vehicle may then be towed in an
emergency.
An outside air source can be used only if the protected system is in
operating condition. If air pressure cannot be restored in the protected
air system, the spring-actuated brakes must be released manually.PARKING
BRAKE
PULL TO
RELEASE
APPLY
PUSH TO
P
BRAKE
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Releasing spring brake manually
Do not attempt to disassemble the parking brake chamber under
any circumstances. The high spring load may cause serious
injury if the chamber clamps are removed.
If air pressure is released from the spring brake chamber the power
spring applies the brake and, unless air pressure can be re-established,
the spring brake must be released as follows in order to move the
vehicle.
Block the wheels to help prevent the vehicle from moving.
Unexpected and possibly sudden vehicle movement may occur if
these precautions are not taken.
Impact wrenches should not be used as they may damage the piston and
prevent proper caging of the spring. Do not apply more than 50 lbs. ft.
(68 N•m) torque to the release bolt nut.
1. Remove the stud tool and nut
from the carrying pocket on the
brake chamber assembly.
2. Remove the access plug from the
end of the spring chamber.
3. Insert the release stud through
the opening in the chamber and into
the spring pressure plate.
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