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WARNING!
Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
NOTE:The engine may run rough until the air is forced
from all the fuel lines.
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.
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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
Observe the following when the engine is operating.
²All message center lights are off.
²Check Engine Lamp is off.
²Engine Oil Pressure is above 10 psi (69 kPa) at idle.
²Low Oil Pressure light is off.
²Voltmeter Operation:
²The voltmeter may show a gauge fluctuation if
certain engine temperatures are below 66ÉF (19ÉC).
This cycling operation is caused by the post-heatcycle of the intake manifold heater system. The
number of cycles and the length of the cycling
operation is controlled by the engine control mod-
ule, this time will not exceed 150 seconds. The
needle should then stabilize at the approximate
operation point.
²The cycling action will cause temporary dimming of
the headlamps, interior lamps, and also a noticeable
reduction in blower motor speed.
Cold Weather Precautions
Operation in ambient temperature below 32ÉF (0ÉC) may
require special considerations. The following charts sug-
gest these options:
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Arctic Operation
Where there are no provisions to keep the engine warm
when it is operating in ambient temperatures consistently
below (-10ÉF/-23ÉC), use 5W-40syntheticengine oil and
fuel that meets the requirements in Section 7, ªMainte-
nance Procedures,º Engine Oil Selection.
Engine Warm-Up
Avoid full throttle operation when the engine is cold.
When starting a cold engine, bring the engine up to
operating speed slowly to allow the oil pressure to
stabilize as the engine warms up.
NOTE:High-speed, no-load running of a cold engine
can result in excessive white smoke and poor engine
performance. No-load engine speeds should be kept
under 1,200 rpm during the warm-up period, especially
in cold ambient temperature conditions.If temperatures are below 32ÉF (0ÉC), operate the engine
at moderate speeds for 5 minutes before full loads are
applied.
Engine Idling Ð In Cold Weather
Avoid prolonged idling. Long periods of idling may be
harmful to your engine because combustion chamber
temperatures can drop so low that the fuel may not burn
completely. Incomplete combustion allows carbon and
varnish to form on piston rings and injector nozzles.
Also, the unburned fuel can enter the crankcase, diluting
the oil and causing rapid wear to the engine.
NOTE:
²If ambient temperatures are low and the coolant
temperature is below 200ÉF (93ÉC), the engine idle
speed will slowly increase to 1000 RPM after 2 minutes
of idle, if the following conditions are met:
²foot is off brake pedal and throttle pedal
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²automatic transmission is in Park (P)
²vehicle speed is zero
²Applying the throttle will cancel fast idle
²If the engine is equipped with an aftermarket exhaust
brake (manual transmissions only), operating the ex-
haust brake at idle will greatly improve warm up rate
and will help keep the engine close to operating
temperature during extended idle.
Stopping The Engine
Idle the engine a few minutes before routine shutdown.
After full load operation, idle the engine 3 to 5 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 important for turbo-
charged, charge air cooled engines, like your Turbo Ram.
Driving
ConditionLoadTurbo-
charger
TemperatureIdle Time
(min.) Be-
fore Engine
Shutdown
Stop and
GoEmpty Cool Less than
One
Stop and
GoMedium One
Highway
SpeedsMedium Warm Two
City Traffic Maximum
GCWRThree
Highway
SpeedsMaximum
GCWRFour
Uphill
GradeMaximum
GCWRHot Five
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Engine Speed Control
CAUTION!
Prevent overspeeding the engine going down hill.
When descending steep grades, use a combination of
gears and service brakes to control vehicle/engine
speed. Overspeed can cause severe engine damage.
Operating Precautions
Avoid Overheating The Engine
The temperature of the coolant (a mixture of 50%
ethylene-glycol and 50% water) must not exceed the
normal range of the temperature gauge (240ÉF/116ÉC)
with a 16 psi (110 kPa) radiator cap.
Usually the coolant temperature indicated during opera-
tion will be to the left of center in the normal range of the
gauge.
Avoid Low Coolant Temperature Operation
Continual operation at low coolant temperature below
the normal range on the gauge (140ÉF/60ÉC) can be
harmful to the engine. Low coolant temperature can
cause incomplete combustion which allows carbon and
varnish to form on piston rings 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 Ð Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
²City Driving Ð
when stopped, put transmission in neutral and increase
engine idle speed.
NOTE:The engine speed will automatically increase to
1000 RPM at elevated coolant temperature to improve
engine cooling.
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ª1º First
Use this position for driving up very steep hills and for
engine braking at low speeds 20 mph (32 km/h) or less
when going downhill. To prevent excessive engine speed,
do not exceed 25 mph (40 km/h) in this range.
NOTE:Use caution when operating a heavily loaded
vehicle in ª2º Second or ª1º First gear selections in high
ambients as torque converter slip can impose significant
additional heat load on the cooling system.
WARNING!
Never use Park position on an automatic transmis-
sion as a substitute for the parking brake. Always
apply parking brake fully when parked to guard
against vehicle movement and possible injury or
damage.
Overdrive Operation
The four-speed overdrive automatic transmission con-
tains an electronically controlled fourth speed (Over-
drive). The transmission will automatically shift from
Drive to Overdrive if the following conditions are
present:
²the transmission selector is in Drive;
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²the engine coolant has reached normal operating tem-
perature;
²vehicle speed is above approximately 30 mph (48
km/h);
²the ªTOW/HAULº switch has not been activated;
²transmission has reached normal operating tempera-
ture.
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).
Overdrive can be locked out by pressing the ªTOW/
HAULº button located on the selector lever. The ªTOW/
HAULº light will illuminate in the instrument cluster to
indicate that the switch has been activated. Pressing the
switch a second time restores the Overdrive function. If
the ªTOW/HAULº feature is desired, theªTOW/HAULº
button must be pressed each time the engine is started.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 temperature. 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 ªTOW/HAULº
and/or TRANS TEMP light(s) may illuminate and the
transmission may downshift out of Overdrive until the
transmission cools down. After cooldown, the transmis-
sion will resume normal operation.
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
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occurs, press the ªTOW/HAULº 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
the engine speed is higher when the torque converter
clutch is not engaged, it may seem as if the transmission
is not shifting into Overdrive when cold. This is normal.Pressing the ªTOW/HAULº button, when the transmis-
sion is sufficiently warm, will demonstrate that the
transmission is able to shift into and out of overdrive.
NOTE:If the vehicle has not been driven in several
days, the first few seconds of operation after shifting the
transmission into gear may seem sluggish. This is due to
the fluid partially draining from the torque converter into
the transmission. This condition is normal and will not
cause damage to the transmission. The torque converter
will refill within five seconds of shifting from Park into
any other gear position.
Manual Transmission ± 5±Speed (NV- 4500) Ð If
Equipped
NOTE:The parking brake should be engaged before
leaving the vehicle, especially on an incline.
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