2004 DODGE RAM 2500 DIESEL oil

speeds will reduce fogging. Interior fogging on the
windshield can be quickly removed by selecting the
defrost mode.
Regular cleaning of the inside of the windows with a
non-filming cleaning solution (vinegar and water works
very well) will help prevent contaminates (cigarette
smoke, perfumes, etc.) from sticking to the windows.
Contaminates increase the rate of window fogging.
Summer Operation
Air conditioned vehicles must be protected with a high
quality antifreeze coolant during summer to provide
proper corrosion protection and to raise the boiling point
of the coolant for protection against overheating. A 50 %
concentration is recommended. Refer to Recommended
Fluids and Genuine Parts for the proper coolant type.
When using the air conditioner in extremely heavy traffic
in hot weather especially when towing a trailer, addi-
tional engine cooling may be required. If this situation isencountered, operate the transmission in a lower gear to
increase engine RPM, coolant flow and fan speed. When
stopped in heavy traffic, it may be necessary to shift into
NEUTRAL and depress the accelerator slightly for fast
idle operation to increase coolant flow and fan speed.
NOTE:On models equipped with Diesel engines, the
idle speed will automatically increase to 1000 rpm at
elevated coolant temperatures to improve engine cooling.
Your air conditioning system is also equipped with an
automatic recirculation system. When the system senses
a heavy load or high heat conditions, it may use partial
Recirculation A/C mode to provide additional comfort.
Winter Operation
When operating the system during the winter months,
make sure the air intake, located directly in front of the
windshield, is free of ice, slush, snow, or other obstruc-
tions.
UNDERSTANDING YOUR INSTRUMENT PANEL 197
4

NTrailer Towing Ð Hitches...............275
NConnecting Trailer Lighting And Electric
Trailer Brakes........................276
NTrailer Weight And Trailer Tongue Weight....278
NTrailer Towing Information
(Maximum Trailer Weight Ratings).........279
NTrailer Towing Mirrors Ð If Equipped......279
NCooling System Tips Ð Trailer Towing......280
NAutomatic Transmission Oil Temperature
Warning Light.......................281
NTowing With An Automatic Transmission....281
mSnowplow............................282
NBefore Plowing.......................283
NSnowplow Prep Package Model Availability . . 283NOver The Road Operation With Snowplow
Attached...........................284
NMethods For Removing Snow............284
NOperating Tips.......................284
NGeneral Maintenance...................285
mRecreational Towing Ð 4±Wheel Drive Vehicles
(Behind Motorhome, Etc.).................286
NRecreational Towing Procedure Ð Manual
Shift Transfer Case Ð If Equipped.........286
NReturning To Normal Operation Ð Manual
Shift Transfer Case....................287
NRecreational Towing Procedure Ð Electronic
Shift Transfer Case Ð If Equipped.........288
NReturning To Normal Operation Ð Electronic
Shift Transfer Case....................290
202 STARTING AND OPERATING

ACC
Allows the electrical accessories to be used when the
engine is not running.
Manual Transmission Key Release Button
To remove the key on vehicles equipped with manual
transmissions, turn the key to the Lock position and press
the button to remove the ignition key.
Key Reminder
An alarm will sound to remind you if the key is left in the
ignition and the driver's door is opened.
STARTING PROCEDURES
The Cummins Diesel engine is equipped with several
features designed to assist cold weather starting and
operation:
²The engine block heater is a resistance heater installed
in the water jacket of the engine just above and behind
the oil filter. It requires a 110±115 volt AC electrical
outlet with a grounded, three-wire extension cord.
NOTE:The engine block heater cord is a factory in-
stalled option. If your vehicle is not equipped, heater
cords are available from your authorized Mopartdealer.
²A 12±volt heater built into the fuel filter housing aids
in preventing fuel gelling. It is controlled by a built-in
thermostat.
STARTING AND OPERATING 205
5

CAUTION!
Do not crank engine for more than 15 seconds at a
time as starter motor damage may result. Turn key to
OFF and wait at least two minutes before trying
again.
5. When the engine starts, release the key.
6. Check to see that there is oil pressure.
7. Release the parking brake.
Starting Procedure Ð Engine Manifold Air
Temperature Below 66ÉF (19ÉC)
NOTE:The temperature displayed on the overhead
console (if equipped) does not necessarily reflect the
engine manifold air temperature. The wait-to-start lamp
will illuminate momentarily for a bulb check when the
ignition key is turned to the ON position, however whencertain engine temperatures fall below 66ÉF (19ÉC) the
lamp will remain on indicating the intake manifold
heater system is active.
Follow the steps in the Normal Starting Procedure ex-
cept:
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.
²The WAIT TO START light will remain on for a period
of time (length of time depends on engine tempera-
ture) after completion of the bulb check.
STARTING AND OPERATING 207
5

²After the WAIT TO START light goes off, turn the
ignition key to START. Do not press the accelerator
during starting.
²Check to see that there is oil pressure.
²Allow the engine to idle at fast idle for about three
minutes until the manifold heaters have completed
the post-heat cycle.
²Release 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 and the back On. Repeat steps 3
through 7 of the normal starting procedure.
For Extremely Cold Weather Starting (Engine
Temperature Below 0ÉF (- 18ÉC)
In extremely cold weather below 0ÉF (- 18ÉC) it may be
beneficial to cycle the manifold heaters twice before
attempting to start the engine. This can be accomplished
by turning the ignition OFF 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.
²If the engine stalls after the initial start, the ignition
must be turned to the OFF position 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.
208 STARTING AND OPERATING

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:
STARTING AND OPERATING 211
5

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
A.Temperatures below 0ÉF (-18ÉC)
²Block Heater Required for 15W-40
²Block Heater Recommended for 5W-40
B.Temperatures below - 20ÉF (-29ÉC)
²Block Heater Required for 5W-40
Winter Front Usage
If a winter front or cold weather cover is to be used, a
percentage of the total grille opening area must be left
uncovered to provide sufficient air flow to the charge air
cooler and automatic transmission oil cooler. The per-
centage of opening must be increased with the increasing
ambient air temperature and/or engine load. If the
cooling fan can be heard cycling frequently, increase the
size of the opening in the winter front. A suitable cold
weather cover is available from your Mopartdealer.
Battery Blanket Usage
A battery loses 60% of its cranking power as the battery
temperature decreases to 0ÉF (-18É). For the same de-
crease in temperature, the engine requires twice as much
power to crank at the same RPM. The use of 120 VAC
powered battery blankets will greatly increase starting
capability at low temperatures. Suitable battery blankets
are available from your authorized Mopartdealer.
STARTING AND OPERATING 213
5

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
214 STARTING AND OPERATING