•Vary throttle position at highway speeds when carry-
ing or towing significant weight.
NOTE: Light duty operation such as light trailer towing
or no load operation will extend the time before the
engine is at full efficiency. Reduced fuel economy and
power may be seen at this time.
For additional vehicle break-in requirements, refer to
“Trailer Towing” in “Starting and Operating” of the
Owners Manual. Because of the construction of the Cummins
turbo-
charged diesel engine, engine run-in is enhanced by
loaded operating conditions which allow the engine
parts to achieve final finish and fit during the first
6,000 miles (10 000 km).
2
THINGS TO KNOW BEFORE STARTING YOUR VEHICLE 7
INSTRUMENT CLUSTER DESCRIPTION
1. Tachometer
The tachometer indicates engine speed in revolutions per
minute.
CAUTION!
Do not operate the engine with the tachometer
pointer at high RPM for extended periods. Engine
damage may occur.
2. Turn Signal Indicator Light The arrow will flash with the exterior turn signal
when the turn signal lever is operated.
NOTE:
•A continuous chime will sound if the vehicle is driven
more than 1 mile (1.6 km) with either turn signal on.
•Check for an inoperative outside light bulb if either
indicator flashes at a rapid rate.
3. Fuel Gauge
Shows level of fuel in tank when ignition switch is in the
ON position.
4. Temperature Gauge
The temperature gauge shows engine coolant tempera-
ture. Any reading within the normal range indicates that
the engine cooling system is operating satisfactorily.
The gauge pointer will likely indicate a higher tempera-
ture when driving in hot weather, up mountain grades,
or when towing a trailer. It should not be allowed to
exceed the upper limits of the normal operating range.
3
UNDERSTANDING YOUR INSTRUMENT PANEL 11
Although your vehicle will usually be drivable and not
need towing, see your authorized dealer for service as
soon as possible.
CAUTION!
Prolonged driving with the MIL on could cause
damage to the engine control system. It also could
affect fuel economy and drivability.
21. Airbag Warning Light This light turns on and remains on for six to
eight seconds as a bulb check when the ignition
switch is first turned ON. If the light is not on
during starting, stays on, or turns on while
driving, have the system inspected by an authorized
dealer as soon as possible. 22. Front Fog Light Indicator Light – If Equipped
This indicator will illuminate when the front fog
lights are on.
23. Anti-Lock Brake (ABS) Warning Light This light monitors the Anti-Lock Brake System
(ABS). The light will turn on when the ignition
switch is turned to the ON position and may
stay on for as long as four seconds.
If the “ABS Warning Light” remains on or turns on while
driving, it indicates that the anti-lock portion of the brake
system is not functioning and that service is required.
However, the conventional brake system will continue to
operate normally if the “Brake Warning Light” is not on.3
UNDERSTANDING YOUR INSTRUMENT PANEL 19
•Electronic Speed Control Indicator LightThis light will turn on when the electronic
speed control is ON.
•Electronic Throttle Control (ETC) Warning LightThis light informs you of a problem with the
Electronic Throttle Control (ETC) system. The
light will come on when the ignition is first
turned ON and remain on briefly as a bulb
check. If the light does not come on during starting, have
the system checked by an authorized dealer.
If a problem is detected, the light will come on while the
engine is running. Cycle the ignition key when the
vehicle has completely stopped and the shift lever is
placed in the PARK position. The light should turn off. If the light remains lit with the engine running your
vehicle, will usually be drivable, however, see an autho-
rized dealer for service as soon as possible. If the light is
flashing when the engine is running, immediate service is
required and you may experience reduced performance,
an elevated/rough idle or engine stall and your vehicle
may require towing.
•Engine Temperature Warning Light
This light warns of an overheated engine condi-
tion. This indicator will illuminate and a single
chime will sound after reaching a set threshold.
Further overheating will cause the indicator to continu-
ously flash and a continuous chime will occur until the
engine is allowed to cool.
If the light turns on while driving, safely pull over and
stop the vehicle. If the A/C system is on, turn it off. Also,
shift the transmission into NEUTRAL and idle the ve-
hicle. If the temperature reading does not return to
3
UNDERSTANDING YOUR INSTRUMENT PANEL 25
normal, turn the engine off immediately and call for
service. Refer to “What To Do In Emergencies/If Your
Engine Overheats” in the Owner’s Manual for more
information.
•SERV 4WD Warning LightThis light monitors the electric shift 4WD sys-
tem. If the SERV 4WD warning light stays on or
comes on during driving, it means that the
4WD system is not functioning properly and
that service is required.
•Transmission Temperature Warning Light This light indicates that there is excessive trans-
mission fluid temperature that might occur
with severe usage such as trailer towing. It may
also occur when operating the vehicle in a high
torque converter slip condition, such as four-wheel drive
operation (e.g., snow plowing, off-road operation). If this light comes on, stop the vehicle and run the engine at idle
or faster, with the transmission in NEUTRAL until the
light goes off.
CAUTION!
Continuous driving with the “Transmission Tem-
perature Warning Light” illuminated will eventually
cause severe transmission damage or transmission
failure.
WARNING!
In some circumstances, the “Transmission Tempera-
ture Warning Light” under continued operation,
could cause the fluid to boil over, come in contact
with hot engine or exhaust components and cause a
fire.
26 UNDERSTANDING YOUR INSTRUMENT PANEL
Diesel Exhaust Fluid (DEF) Fault Warning
Messages – Chassis Cab Only
There are three different messages if the vehicle detects
that the DEF system has been filled with a fluid other
than DEF, component failures, or tampering has been
detected. The vehicle will not start if the DEF system is
not serviced within 750 miles (1 207 km) of the fault being
detected.
When the DEF system needs to be serviced the following
warnings will display:
•Service DEF System – See Dealer— This message
will display when the fault is initially detected, each
time the vehicle is started, and periodically during
driving. The message will be accompanied by a single
chime. We recommend you drive to your nearest
authorized dealer and have your vehicle serviced as
soon as possible.
•Service DEF System Engine Will Not Start In
500 Miles – See Dealer — This message will display if
the DEF system has not been serviced within 250 miles
after the “Service DEF System – See Dealer” message is
displayed. This message will continuously display
until the mileage counter reaches zero, and will be
accompanied by a periodic chime. The message will
continue to countdown until it reaches zero unless the
vehicle is serviced. We recommend you drive to your
nearest authorized dealer and have your vehicle ser-
viced immediately.
•Service DEF System Engine Will Not Start – See
Dealer — This message will continuously display
when the mileage counter reaches zero, and will be
accompanied by a periodic chime. The engine will not
restart after it has been turned off, your vehicle will
require towing, see your authorized dealer for service.
3
UNDERSTANDING YOUR INSTRUMENT PANEL 29
WARNING!
Do not use the exhaust brake feature when driving in
icy or slippery conditions as the increased engine
braking can cause the rear wheels to slide and the
vehicle to swing around with the possible loss of
vehicle control, which may cause an accident possi-
bly resulting in personal injury or death.
NOTE: For optimum braking power it is recommended
to use the exhaust brake while in TOW/HAUL mode.
The purpose of the exhaust brake (engine braking) fea-
ture is to supply negative (braking) torque to the engine.
Typically, the engine braking is used for, but not limited
to, vehicle towing applications where vehicle braking can
be achieved by the internal engine power, thereby spar-
ing the mechanical brakes of the vehicle. Benefits of the exhaust brake are:•vehicle driving control
•reduced brake fade
•longer brake life
•faster cab warm-up.
The exhaust brake feature can also be used to reduce the
engine warm up time. To use the exhaust brake as a
warm-up device, the vehicle must be stopped or moving
less than 5 mph (8 km/h), the exhaust brake switch must
be in the ON position, and the coolant temperature must
be below 180°F (82°C) and ambient temperature below
60°F (16°C).
4
STARTING AND OPERATING 59
•transmission has reached normal operating
temperature.
NOTE: If the vehicle is started in extremely cold tem-
peratures, the transmission may not shift into Overdrive
and will automatically select the most desirable gear for
operation at this temperature. Normal operation will
resume when the transmission fluid temperature has
risen to a suitable level. Refer to the “Note” under
“Torque Converter Clutch” later in this section.
If the transmission temperature gets extremely hot, the
transmission will automatically select the most desirable
gear for operation at this temperature. If the transmission
temperature becomes hot enough the “Transmission
Temperature Warning Light” may illuminate and the
transmission may downshift out of Overdrive until the
transmission cools down. After cool down, the transmis-
sion will resume normal operation. The transmission will downshift from Overdrive to
DRIVE if the accelerator pedal is fully pressed at vehicle
speeds above approximately 35 mph (56 km/h).
When To Use TOW/HAUL
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the “TOW/HAUL” switch once to select
“TOW/HAUL.” In “TOW/HAUL” mode, fourth to fifth
gear upshifts are delayed. Shifts into fifth and sixth gear
are still allowed under steady cruise conditions. Closed
throttle downshifts (for improved engine braking) may
occur during steady braking maneuvers. Pressing the
switch a second time restores normal operation. Normal
operation is always the default at engine start-up.
66 STARTING AND OPERATING