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CAUTION!
Do not crank engine for more than 15 seconds at a
time or starter motor damage may result. Turn key to
OFF and wait at least 2 minutes for starter to cool
before repeating start procedure.
•The WAIT TO START light will remain on for a period
of time (length of time depends on engine tempera-
ture).
•After the WAIT TO START light goes off, turn the
ignition key to START. Do not press the accelerator
during starting.
•After engine start-up, check to see that there is oil
pressure.
•Allow the engine to idle about three minutes until
the manifold heaters have completed the post-heat
cycle.
•Release the parking brake and drive.
NOTE: Engine idle speed will automatically increase to
1000 rpm at low coolant temperatures to improve engine
warm-up.
NOTE: If the engine stalls or if the ignition switch is left
On for more than 2 minutes after the WAIT TO START
light goes out, reset the grid heaters by turning the
ignition switch to Off for at least 5 seconds and then back
On. Repeat steps 3 through 7 of the normal starting
procedure.
For Extremely Cold Weather Starting — Engine
Manifold Air Temperature Below 0°F (- 18°C)
In extremely cold weather below 0°F (- 18°C) it may be
beneficial to cycle the manifold heaters twice before
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attempting to start the engine. This can be accomplished
by turning the ignition OFF for at least 5 seconds and
then back ON after the WAIT TO START light has gone
off, but before the engine is started. However, repeated
cycling of the manifold heaters will result in damage to
the heater elements or reduced battery voltage.
NOTE: If multiple pre-heat cycles are used before
starting, additional engine run time may be required to
maintain battery state of charge at a satisfactory level.
•If the engine stalls after the initial start, the ignition
must be turned to the OFF position for at least 5
seconds and then to the ON position to recycle the
manifold heaters.
NOTE: Excessive white smoke and poor engine perfor-
mance will result if manifold heaters are not recycled.
•Heat generated by the manifold heaters dissipates
rapidly in a cold engine. If more than two minutes pass between the time the WAIT TO START light goes
OFF and the engine is started, recycle the manifold
heaters by turning the ignition OFF for at least 5
seconds and then back ON.
•If the vehicle is driven and vehicle speed exceeds 19
mph (31 km) before the manifold heater post-heat
(after start) cycle is complete, the manifold heaters will
shut off.
•If the engine is started before the WAIT TO START
light turns off, the preheat cycle will turn off.
•If the engine is cranked for more than 10 seconds, the
post-heat cycle will turn off.
NOTE: Engine idle speed will automatically increase to
1000 rpm at low coolant temperatures to improve engine
warm-up.
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Starting Fluids
WARNING!
STARTING FLUIDS or flammable liquids are
NEVER TO BE USED in the Cummins Diesel (see
Warning label). Never pour diesel fuel, flammable
liquid, starting fluids (ether) into the air cleaner
canister, air intake piping, or turbocharger inlet in an
attempt to start the vehicle. This could result in a
flash fire and explosion causing serious personal
injury and engine damage.
The engine is equipped with an automatic electric air
preheating system. If the instructions in this manual are
followed, the engine should start in all conditions.
WARNING!
Do not leave children or animals inside parked
vehicles in hot weather. Interior heat build up may
cause serious injury or death.
NORMAL OPERATION (DIESEL ENGINE)
Observe the following when the engine is operating.
•All message center lights are off.
•Check Engine Lamp is off.
•Engine Oil Pressure is above 10 psi (69 kPa) at idle.
•Low Oil Pressure light is off.
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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 also 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 TRANS TEMP light
may illuminate and the transmission may downshift out
of Overdrive until the transmission cools down. After
cooldown, the transmission will resume normal opera-
tion.
The transmission will downshift from Overdrive to Drive
if the accelerator pedal is fully depressed at vehicle
speeds above approximately 35 mph (56 km/h).When To Use “TOW HAUL” and “O/D OFF”
Modes
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the “TOW HAUL O/D OFF” button once to
select TOW HAUL. This will improve performance and
Tow Haul O/D Off Switch
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reduce the potential for transmission overheating or
failure due to excessive shifting. When operating in
“TOW HAUL” mode, 5th gear (if equipped) is disabled
and 2-3 and 3-4 shift patterns are modified. Shifts into
Overdrive (4th gear) are allowed during steady cruise
(for improved fuel economy) and automatic closed-
throttle downshifts to 3rd gear (for improved braking)
will occur during steady braking. Pressing the “TOW
HAUL O/D OFF” button a second time to select O/D
OFF will disable 4th and 5th gear completely, which
should eliminate any excessive transmission shifting.
The “TOW HAUL” or “O/D OFF” light will illuminate in
the instrument cluster to indicate when the switch has
been activated. Pressing the switch a third time restores
normal operation. If the “TOW HAUL” or “O/D OFF”
modes are desired, the button must be pressed each time
the engine is started.When To Lock Out Overdrive
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent 4–3–4 transmission shifting
occurs, press the “TOW/HAUL” button. This will im-
prove performance and reduce the potential for transmis-
sion overheating or failure due to excessive shifting.
Torque Converter Clutch
A feature, designed to improve fuel economy, has been
included in the automatic transmission on your vehicle.
A clutch within the torque converter engages automati-
cally at calibrated speeds. This may result in a slightly
different feeling or response during normal operation in
high gear. When the vehicle speed drops or during
acceleration when the transmission downshifts to second
gear, the clutch automatically disengages.
NOTE: The torque converter clutch will not engage
until the transmission fluid and engine coolant are warm
[usually after 1-3 miles (1.6 - 4.8 km) of driving]. Because
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The alarm will continue for 3 minutes if the driver’s door
is closed but none of the other conditions listed above are
met.
MANUAL TRANSMISSION
WARNING!
You or others could be injured if you leave the
vehicle unattended without having the parking
brake fully applied. The parking brake should al-
ways be applied when the driver is not in the
vehicle, especially on an incline.
Truck models with manual transmission are equipped
with a clutch interlocking ignition system. The clutch
pedal must be fully depressed to start the vehicle. Fully depress the clutch pedal before shifting gears. As
you release the clutch pedal, lightly depress the accelera-
tor pedal.
This transmission has a “creeper” 1st gear which should
be used to start from a standing position when carrying
a payload or towing a trailer. Damage to the clutch can
result from starting in 2nd or 3rd gear with a loaded
vehicle. An unloaded vehicle may be launched in 2nd
gear. Use each gear in numerical order – do not skip a
gear.
For most city driving you may find it easier to use only
1st through 5th gear ranges. For steady highway driving
with light accelerations, 6th gear is recommended. To
shift into 5th gear, move the shift lever to the right
beyond the spring pressure point and push it forward.
When shifting from 5th to 4th gear, pull the lever down
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The 4-wheel-drive light (4WD), located in the instrument
cluster, alerts the driver that the vehicle is in 4-wheel
drive and that the front and rear driveshafts are locked
together. This light illuminates when the transfer case is
shifted to either the 4H or 4L positions. There is no light
for the 2H or N (Neutral) positions.
When operating your vehicle in 4L, the engine speed is
approximately three times that of the 2H or 4H positions
at a given road speed. Take care not to overspeed the
engine and do not exceed 25 mph (40 km/h).
Proper operation of 4-wheel-drive vehicles depends on
tires of equal size, type and circumference on each wheel.
Any difference will adversely affect shifting and can
cause damage to the transfer case. NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning. The transfer case is not
equipped with a synchronizer and therefore the front and
rear driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case.
Because 4-wheel drive provides improved traction, there
is a tendency to exceed safe turning and stopping speeds.
Do not go faster than road conditions permit.
NOTE: Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or uneven tire
pressures, excessive vehicle loading, or cold tempera-
tures.
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NOTE:Shifting into or out of 4L is possible with the
vehicle completely stopped, however difficulty may oc-
cur due to the mating clutch teeth not being properly
aligned. Several attempts may be required for clutch
teeth alignment and shift completion to occur. The pre-
ferred method is with the vehicle rolling 2 to 3 mph (3 to
5 km/h). Avoid attempting to engage or disengage 4L
with the vehicle moving faster than 2 to 3 mph (3 to 5
km/h).
NOTE: Do not attempt to shift to or from 4L while the
transmission is in gear or clutch is engaged.
Transfer Case Reminder Light
The four-wheel-drive operating light (4WD), located in
the instrument cluster, is used to alert the driver that the
front axle is fully engaged and all four wheels are
driving.
Electronically Shifted Transfer Case Operating
Information/Precautions–If Equipped
This is an electric shift transfer case and is operated by
the 4WD Control Switch (Transfer Case Switch), which is
located on the instrument panel.
Transfer Case Switch
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