2008 DODGE RAM 3500 DIESEL TOWING

9. Oil Pressure Gauge
The pointer should always indicate some oil pres-
sure when the engine is running. A continuous
high or low reading, under normal driving conditions,
may indicate a lubrication system malfunction. Immedi-
ate service should be obtained.
NOTE:If the gauge pointer moves to either extreme of
the gauge, the ªCheck Gaugesº indicator will illuminate
and a single chime will sound.
10. Transfer Case Position
This display indicator shows the transfer case position
selection.
For additional information refer to ªFour-Wheel Drive
Operationº in Section 5 of this manual.11 .TOW HAUL
The TOW HAUL button is located at the end of the gear
shift lever. This light will illuminate when the TOW
HAUL button is pushed once.
12. Temperature Gauge
The temperature gauge indicates engine coolant
temperature. Any reading within the normal
range indicates that the cooling system is operat-
ing satisfactorily. The gauge needle will likely indicate a
higher temperature when driving in hot weather, up
mountain grades, in heavy traffic, or when towing a
trailer. If the needle rises to the ª245ÉFº (118ÉC) mark,
stop the vehicle, shift into NEUTRAL, and increase the
engine idle speed for two to three minutes. If the tem-
perature reading does not return to normal, shut your
engine OFF and allow it to cool. Seek authorized service
immediately. Refer to ªCooling Systemº under ªMain-
taining Your Vehicleº in Section 7.
UNDERSTANDING YOUR INSTRUMENT PANEL 191
4

17. Malfunction Indicator Light (MIL)
This light is part of an onboard diagnostic system
which monitors the emissions and engine control
system. If the vehicle is ready for emissions
testing the light will come on when the ignition is first
turned on and remain on, as a bulb check, until the
engine is started. If the vehicle is not ready for emissions
testing the light will come on when the ignition is first
turned on and remain on for 15 seconds, then blink for
five seconds, and remain on until the vehicle is started. If
the bulb does not come on during starting, have the
condition investigated promptly.
If this light comes on and remains on while driving, it
suggests a potential engine control problem and the need
for system service.
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.
If the MIL is flashing, severe catalytic converter
damage and power loss will soon occur. Immediate
service is required.
18. Brake System Warning Light
This light illuminates when the ignition key is turned to
the ON position and remains on for a few seconds. If the
light stays on longer, it may be an indication that the
parking brake has not been released. This light will
illuminate if the brake fluid is low, especially when
braking or accelerating hard. This light will illuminate if
the ABS indicator light has a malfunction. This light will
flash if the engine is running and the parking brake is on.
194 UNDERSTANDING YOUR INSTRUMENT PANEL

experience reduced performance, an elevated/rough idle
or engine stall and your vehicle may require towing. The
light will come on when the ignition is first turned on
and remain on for 15 seconds as a bulb check. If the light
does not come on during starting, have the system
checked by an authorized dealer.
22. SERV 4WD Indicator
The 4WD indicator will be illuminated whenever the
4WD mode is engaged for either the manual or electric
shift 4WD systems. The SERV 4WD indicator monitors
the electric shift 4WD system. If the SERV 4WD light
stays on or comes on during driving, it means that the
4WD system is not functioning properly and that service
is required.23. Water In Fuel Indicator
Indicates there is water detected in the fuel
filter. Refer to the Maintenance section, Drain-
ing Fuel/Water Separator Filter, for water
drain procedure.
24. Tire Pressure Monitoring Telltale Light Ð If
Equipped
Each tire, including the spare (if provided),
should be checked monthly when cold and
inflated to the inflation pressure recommended
by the vehicle manufacturer on the vehicle
placard or tire inflation pressure label. (If your vehicle
has tires of a different size than the size indicated on the
vehicle placard or tire inflation pressure label, you should
determine the proper tire inflation pressure for those
tires.)
196 UNDERSTANDING YOUR INSTRUMENT PANEL

CAUTION!
The TPMS has been optimized for the original
equipment tires and wheels. TPMS pressures and
warning have been established for the tire size
equipped on your vehicle. Undesirable system opera-
tion or sensor damage may result when using re-
placement equipment that is not of the same size,
type, and/or style. Aftermarket wheels can cause
sensor damage. Do not use tire sealant from a can, or
balance beads if your vehicle is equipped with a
TPMS, as damage to the sensors may result.
TPMS ªLight Loadº Reset Switch ± If Equipped
The TPMS ºLight Loadº reset switch allows you to
choose between Light Load vehicle conditions and Max
Load vehicle conditions tire pressures and related TPMS
warning levels. The switch is located in the instrumentpanel, below the climate control panel. For additional
information refer to ªTire Pressure Monitoring System
(TPMS) Ð If Equippedº in section 5 of this manual.
25. Transmission Oil Temperature Warning Light
(Automatic Transmissions Only)
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 4-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.
26. Wait To Start Indicator
The Wait To Start indicator will illuminate when
the ignition is turned to the run position and the
intake manifold temperature is below 66ÉF (19ÉC).
198 UNDERSTANDING YOUR INSTRUMENT PANEL

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. For proper coolant type,
refer to ªRecommended Fluids and Genuine Partsº in
Section 7.
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 is
encountered, 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 261
4

mFuel Requirements......................348
NFuel Requirements (6.7L Diesel Engines).....348
mAdding Fuel (Diesel Engines)..............349
NFuel Filler Cap (Gas Cap)...............350
NBulk Fuel Storage.....................351
mVehicle Loading........................352
NCertification Label.....................352
mTrailer Towing.........................356
NCommon Towing Definitions.............356
NTrailer Hitch Classification...............360
NTrailer Towing Weights (Maximum Trailer
Weight Ratings)......................361NTrailer And Tongue Weight..............361
NTowing Requirements..................362
NTowing Tips.........................368
NTrailer Towing Mirrors Ð If Equipped......370
mSnowplow............................371
NBefore Plowing.......................372
NSnowplow Prep Package Model Availability . . 372
NOver The Road Operation With Snowplow
Attached...........................373
NMethods For Removing Snow............373
NOperating Tips.......................373
NGeneral Maintenance...................374
266 STARTING AND OPERATING

mRecreational Towing (Behind Motorhome, Etc.) . . 375
NRecreational Towing ± 2-Wheel Drive
Models............................375NRecreational Towing ± 4-Wheel Drive
Models............................375
STARTING AND OPERATING 267
5

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:²vehicle driving control
²reduced brake fade
²longer brake life
²faster 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 moving less than 5
mph (8 km/h), the exhaust brake switch must be in the
ON position, and the coolant temperature must below
180ÉF (82ÉC) and ambient temperature below 60ÉF (16ÉC).
284 STARTING AND OPERATING