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Starting Fluids
WARNING!
Starting fluids or flammable liquids must never be
used in the Cummins diesel engine (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.
• When leaving the vehicle, always remove the key
fob from the ignition and lock your vehicle. If
equipped with Keyless Enter-N-Go, always make
sure the keyless ignition node is in “OFF” mode,
remove the Key Fob from the vehicle and lock the
vehicle.
• Never leave children alone in a vehicle, or with
access to an unlocked vehicle. Allowing children to
be in a vehicle unattended is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Children should be
warned not to touch the parking brake, brake pedal
or the gear selector.
(Continued)
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WARNING!(Continued)
•Do not leave the key fob in or near the vehicle (or
in a location accessible to children), and do not
leave the ignition (of a vehicle equipped with
Keyless Enter-N-Go) in the ACC or ON/RUN
mode. A child could operate power windows, other
controls, or move the vehicle.
NORMAL OPERATION — DIESEL ENGINE
Observe the following when the engine is operating.
• All message center lights are off.
• Malfunction Indicator Light (MIL) is off.
• Engine oil pressure is above 10 psi (69 kPa) at idle. •
Voltmeter operation:
The voltmeter may show a gauge fluctuation at various
engine temperatures. This cycling operation is caused by
the post-heat cycle of the intake manifold heater system.
The number of cycles and the length of the cycling
operation is controlled by the engine control module.
Post-heat operation can run for several minutes, and then
the electrical system and voltmeter needle will stabilize.
The cycling action will cause temporary dimming of the
headlamps, interior lamps, and also a noticeable reduc-
tion in blower motor speed.
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varnish to form on piston rings, engine valves, and
injector nozzles. Also, the unburned fuel can enter the
crankcase, diluting the oil and causing rapid wear to the
engine.
If the engine is allowed to idle, under some conditions
the idle speed may increase to 900 RPM then return to
normal idle speed. This is normal operation.
NOTE:For EVIC/DID messages related to the vehicle’s
exhaust system, refer to “Electronic Vehicle Information
Center (EVIC)” or “Driver Information Display (DID)”
for further information.
Idle-Up Feature — Automatic Transmission Only
The driver-controlled high idle speed feature will help
increase cylinder temperatures and provide additional
cab heat, however, excessive idling may still cause the
exhaust aftertreatment system to not properly regenerate.
Extended periods of idle time should be avoided. The Idle-Up feature uses the speed control switches to
increase engine idle speed and quickly warm the vehi-
cle’s interior.
1. With the transmission in PARK, the parking brake
applied, and the engine running, push the speed
control switch to the ON position, then push the SET
switch.
2. The engine RPM will go up to 1100 RPM. To increase the RPM, push and hold the ACCEL/RESUME switch
and the idle speed will increase to approximately 1500
RPM. To decrease the RPM, push and hold the DECEL
switch and the idle speed will decrease to approxi-
mately 1100 RPM.
3. To cancel the Idle–Up feature, either push the CAN- CEL switch, push the ON/OFF switch, or press the
brake pedal.
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Stopping The Engine
Idle the engine a few minutes before routine shutdown.
After full load operation, idle the engine three to five
minutes before shutting it down. This idle period will
allow the lubricating oil and coolant to carry excess heat
away from the combustion chamber, bearings, internal
components, and turbocharger. This is especially impor-
tant for turbocharged, charge air-cooled engines.NOTE:
•
During engine shut down on vehicles equipped with
manual transmissions, it is normal for the diesel en-
gine to resonate heavily for a moment during engine
shut off. When the engine is connected to a manual
transmission, this resonance causes load gear rattle
from the transmission. This is commonly referred to as
“shut down rattle.” The manufacturer recommends
performing engine shut down with the clutch pedal
pushed to the floor (clutch disengaged). When engine
shut down is performed in this manner the rattle is
reduced (not eliminated).
• Refer to the following chart for proper engine shut-
down.
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Operating Precautions
Avoid Overheating The Engine
The temperature of the engine coolant (antifreeze) (a
mixture of 50% ethylene-glycol and 50% water) must not
exceed the normal range of the temperature gauge 240°F
(116°C) with a 21 psi (145 kPa) coolant pressure cap.
Usually the engine coolant (antifreeze) temperature indi-
cated during operation will be to the left of center in the
normal range of the gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low engine coolant (antifreeze)
temperature below the normal range on the gauge 140°F
(60°C) can be harmful to the engine. Low engine coolant
(antifreeze) temperature can cause incomplete combus-
tion which allows carbon and varnish to form on pistonrings and injector nozzles. Also, the unburned fuel can
enter the crankcase, diluting the lubricating oil and
causing rapid wear to the engine.
Cooling System Tips — Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
•
City Driving —
When stopped, shift the transmission into NEUTRAL
and increase engine idle speed.
• Highway Driving —
Reduce your speed.
• Up Steep Hills —
Select a lower transmission gear.
• Air Conditioning —
Turn it off temporarily.
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Do Not Operate The Engine With Low Oil
Pressure
When the engine is at normal operating temperature, the
minimum oil pressures required are:
Idle 700 to 800 RPM 10 psi (69 kPa)
Full speed and load 30 psi (207 kPa)
CAUTION!
If oil pressure falls to less than normal readings, shut
the engine off immediately. Failure to do so could
result in immediate and severe engine damage.
Do Not Operate The Engine With Failed Parts
All engine failures give some warning before the parts
fail. Be on the alert for changes in performance, sounds,
and visual evidence that the engine requires service.
Some important clues are:•
Engine misfiring or vibrating severely.
• Sudden loss of power.
• Unusual engine noises.
• Fuel, oil or coolant leaks.
• Sudden change, outside the normal operating range, in
the engine operating temperature.
• Excessive smoke.
• Oil pressure drop.
ENGINE BLOCK HEATER — IF EQUIPPED
The engine block heater warms engine coolant and
permits quicker starts in cold weather. Connect the heater
cord to a ground-fault interrupter protected 110–115 Volt
AC electrical outlet with a grounded, three-wire exten-
sion cord.
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The engine block heater cord is routed under the hood to
the right side and can be located just behind the grille
near the headlamp.
NOTE:The engine block heater cord is a factory installed
option. If your vehicle is not equipped, heater cords are
available from your authorized MOPAR dealer.
The block heater must be plugged in at least one hour to
have an adequate warming effect on the coolant.
WARNING!
Remember to disconnect the cord before driving.
Damage to the 110–115 Volt electrical cord could
cause electrocution.
NOTE: The block heater will require 110 Volts AC and 6.5
Amps to activate the heater element.
Block Heater Usage
For ambient temperatures below 0°F (-18°C), engine
block heater usage is recommended.
For ambient temperatures below –20°F (-29°C), engine
block heater usage is required.
DIESEL EXHAUST BRAKE (ENGINE BRAKING)
The purpose of the exhaust brake (engine braking) fea-
ture is to supply negative (braking) torque from 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 sparing the mechanical brakes of the vehicle.
Benefits of the exhaust brake are:
• Vehicle driving control.
• Reduced brake fade.
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Select (ERS) shift control (refer to “Electronic Range
Select (ERS) Operation” in this section for further infor-
mation) to select a lower gear range. Under these condi-
tions, using a lower gear range will improve performance
and extend transmission life by reducing excessive shift-
ing and heat buildup.
If the transmission temperature exceeds normal operat-
ing limits, the powertrain controller will modify the
transmission shift schedule and expand the range of
torque converter clutch engagement. This is done to
prevent transmission damage due to overheating.
If the transmission becomes extremely hot or is in danger
of overheating, the “Transmission Temperature Warning
Light” may illuminate and the transmission may operate
differently until the transmission cools down.NOTE:
Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation.
During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of the torque
converter clutch is inhibited until the transmission fluid
is warm (refer to the “Note” under “Torque Converter
Clutch” in this section). On Pickup models with 68RFE
transmission, top overdrive gear is also inhibited until
the transmission fluid is warm, and during extremely
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