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Do not shift the gearshift lever into N (Neutral) with the speed
control on.
To turn speed control off
Instrument panel-mounted
controls:Press OFF or turn off the
ignition.
Once speed control is switched off,
the previously programmed engine
RPM will be erased.
Steering wheel-mounted
controls:Press OFF or turn off the
ignition.
Once speed control is switched off,
the previously programmed set
speed will be erased.
Do not use the speed control in heavy traffic or on roads that
are winding, slippery, or unpaved.
To set a speed
Instrument panel-mounted
controls:Press SET +. If the
vehicle is moving, this will set the
vehicle speed. If the vehicle is
stationary, this will set the vehicle
idle RPM.
Steering wheel-mounted
controls:Press SET ACCEL. For
speed control to operate, the speed
control must be on and vehicle
speed must be at or above 30 mph
(48 km/h)
CRUISE
RPM
OFF
RES
SET
ACCEL
COAST
Driver controls
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If you drive up or down a steep hill, your vehicle speed may vary
momentarily slower or faster than the set speed; this is normal.
Speed control cannot reduce the vehicle speed if it increases above the
set speed on a downhill. If your vehicle speed is faster than the set
speed while driving on a downhill, you may want to shift to the next
lower gear or apply the brakes to reduce your vehicle speed.
If the vehicle speed falls below 30 mph (48 km/h) or engine RPM falls
below 1,000 RPM, your speed control will disengage; this is normal.
Pressing RESUME - (instrument panel-mounted controls) or RES
(steering wheel-mounted controls) will re-engage it.
Do not use the speed control in heavy traffic or on roads that
are winding, slippery, or unpaved.
To set a higher set speed
Instrument panel-mounted
controls:Press and hold SET +. If
the vehicle is moving, this will
increase vehicle speed; if the vehicle
is stationary, this will increase
engine RPM. Release the control
when the desired vehicle
speed/engine RPM is reached.
Press and release SET + to operate the tap-up function. Each press will
increase the set speed by 1 mph (1.6 km/h) or engine RPM in idle mode.
Steering wheel-mounted
controls:Press and hold SET
ACCEL. Release SET ACCEL when
the desired vehicle speed is
reached. SET ACCEL can also be
pressed and released to operate the
tap-up function which will increase
vehicle speed in increments of 1
mph (1.6 km/h).
You can accelerate with the accelerator pedal at any time during speed
control usage. Releasing the accelerator pedal will return your vehicle to
the previously programmed speed.
RES
SET
ACCEL
COAST
Driver controls
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To set a lower set speed
Instrument panel-mounted
controls:Press and hold RESUME
-. If the vehicle is moving, this will
decrease vehicle speed; if the
vehicle is stationary, this will
decrease engine RPM. Release the
control when the desired vehicle
speed/engine RPM is reached.
Press and release RESUME - to operate the tap-down function. Each
press will decrease the set speed in increments of 1 mph (1.6 km/h) or
engine RPM in idle mode.
Steering wheel-mounted
controls:Press and hold COAST.
Release the control when the
desired vehicle speed is reached.
Press and release COAST to operate
the tap-down function. Each press
wiill decrease the set speed in
increments of 1 mph (1.6 km/h).
SET RESUME
RES
SET
ACCEL
COAST
Driver controls
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To disengage speed control
•Depress the brake pedal or
•Depress the clutch pedal (if
equipped).
Disengaging the speed control will
not erase the previously
programmed set speed or engine
RPM.
Instrument panel-mounted
controls:Pressing OFF will erase
the previously programmed engine
RPM.
Steering wheel-mounted
controls:Pressing OFF will erase
the previously programmed speed.
CRUISE
RPM
OFF
Driver controls
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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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Page 105 of 272

4. Turn the release stud one-quarter
turn to engage the stud tangs with
the slot in the pressure plate. Keep
the stud engaged and install the nut
on the release stud.
5. Tighten the nut until the spring is
fully caged and the brakes are
released. Do not loosen or remove
the release stud and nut unless the brake chamber is completely
assembled and is securely clamped.
6. When the air pressure is restored, unscrew and remove the release
stud and install in the carrying pocket. Install the access plug.
Exhaust brake (if equipped)
Note:The exhaust brake is a
retarding device intended to help
control vehicle speed; it is not a
vehicle stopping device.
An exhaust brake is an optional
auxiliary braking system that assists,
but does not replace, the primary
service brake system. An on-off
switch on the instrument panel, in
combination with the accelerator
and clutch pedal switches, allows the operator to make maximum use of
the exhaust brake in the following conditions:
•off-highway driving
•mountain driving
•heavy traffic
•high speed highway driving
Note:The exhaust brake should be turned off when the engine is left
idling for an extended period of time (longer than three minutes).
Driving
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•Depending on the grade and vehicle load, you may or may not feel the
retarding force acting against your body when the brake is applied.
The brake’s retarding force is actually preventing the vehicle from
going much faster.
•Engine speed has a major effect on retarding performance, with higher
engine speeds permitting greater retarding ability.
•Engine brake performance is closely related to the type of
transmission your vehicle is equipped with. Downshifting of manual
transmission to the lowest gear possible, without exceeding the
maximum engine RPM limit, will maximize retarding performance.
Exhaust brakes will operate effectively with automatic transmissions,
but performance will vary with engine speed and the gear selected by
the transmission.
Make sure the exhaust brake is turned off before shutting off the engine.
Note:Installing an exhaust or auxiliary brake does not necessarily
protect the engine from exceeding maximum governed speed. The
primary brakes should be used to never allow the engine to exceed
maximum governed speed under any conditions.
Trailer brake hand control (if equipped)
The hand control, located on the
right-hand side of the instrument
panel, is used to apply the trailer
service brakes which are
independent of the truck or tractor
service brakes.
The hand control should
never be used to apply the
brakes when the tractor and
trailer are parked unattended. Air
may leak from the system and the
vehicle could possibly move,
resulting in possible property
damage, personal injury or death.
The hand control operates a valve that provides gradual control of air
pressure applied; when the valve is only partially applied, the trailer
brakes can be overridden by pressing fully on the brake pedal.
Driving
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When the Traction Controlswitch, located on the instrument panel, is
in the off position, the traction control light will be illuminated.
If you should become stuck in snow or ice or on a very slippery road
surface, try switching the Traction Controlsystem off. This may allow
excess wheel spin to“dig”the vehicle out and enable a successful
“rocking”maneuver.
Aggressive driving in any road conditions can cause you to lose
control of your vehicle increasing the risk of severe personal
injury or property damage. The occurrence of a Traction Control
event is an indication that at least some of the tires have exceeded
their ability to grip the road; this may lead to an increased risk of loss
of vehicle control, vehicle rollover, personal injury and death. If you
experience a severe road event, SLOW DOWN.
AIR SUSPENSION (IF EQUIPPED)
Note:The vehicle must not be operated without air in the suspension
springs. Operating the vehicle without air in the air suspension springs
will damage the suspension, degrade ride performance and may cause
property damage.
The suspension system automatically adjusts to different loads to
maintain a constant frame height. The system allows for ease of vehicle
loading and provides improved vehicle ride and increased driver comfort.
Air suspension dump switch (if equipped)
The system is controlled by a switch
located on the instrument panel.
The switch will operate only when
the ignition is in the ACC
(Accessory) or IGNITION positions
and the air tanks have sufficient
pressure to fill the air springs. When
the ignition is turned off, the
suspension will remain in whatever
state it was last set.
Note:The suspension will dump air when the ignition is in the ACC or
IGNITION position, but will only fill when the ignition is in the IGNITION
position.
When the upper portion of the switch is pressed and the vehicle speed is
below 5 mph (8 km/h), air supplied to the air spring is exhausted,
Driving
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