2007 DODGE RAM 2500 DIESEL cooling

NOTE:If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
10. Transfer Case Position
(See page 273 for more information.)
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 OD/OFF button is pushed once. (See page 269 for
more information.)
12. OD/OFF
the OD/OFF button is located at the end of the gear shift
lever. This light will illuminate when the TOW HAUL
OD/OFF button is pushed twice. (See page 269 for more
information.) 13. 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 “245°F” mark, stop the
vehicle, shift into N (Neutral), and increase the engine
idle speed for 2 to 3 minutes. If the temperature reading
does not return to normal, shut your engine OFF and
allow it to cool. Seek authorized service immediately. See
Cooling System information in the section on “Maintain-
ing Your Vehicle.”
UNDERSTANDING YOUR INSTRUMENT PANEL 181
4

CAUTION!
Do not leave your vehicle unattended with the
engine running as you would not be able to react to
the temperature indicator if the engine overheats.
NOTE: Engine idle speed will automatically increase to
1000 rpm at elevated coolant temperatures to improve
engine cooling.
NOTE: If the gauge pointer moves to either extreme of
the gauge, the “Check Gages” indicator will illuminate
and a single chime will sound.
14. Security Light
The light will flash rapidly for approximately 16 seconds
when the vehicle theft alarm is arming. The light will
flash at a slower rate after the alarm is set. The security
light will also come on for about two seconds when the
ignition is first turned ON. 15. Transmission Range Indicator (Automatic
Transmissions Only)
When the gear selector lever is moved, this indicator
shows the automatic transmission gear range selected.
16. Odometer/Trip Odometer
The odometer shows the total distance the vehicle has
been driven.
If the odometer reading is changed during repair or
replacement, be sure to keep a record of the reading
before and after the service so that the correct mileage can
be determined.
The trip odometer shows individual trip mileage. To
toggle between the odometer and the trip odometer,
press the Odometer/Trip Odometer Button. To reset the
Trip Odometer, press and hold the button while in trip
mode, until the Trip Odometer resets.
182 UNDERSTANDING YOUR INSTRUMENT PANEL

NOTE:To improve your selection choices, the system
allows you to operate at intermediate positions between
the major modes. These intermediate positions are iden-
tified by the small dots.
Recirculation Modes (Panel or Bi-Level)
Select the recirculation modes when
the outside air contains smoke, odors,
high humidity, or if rapid cooling is
desired. This feature allows for recir-
culation of interior air only. Air flows
through the panel only or through
both the panel and floor vents depend-
ing on the selected mode (panel vs bi-level).
NOTE: Selecting a “Recirculation Mode” mode does not
necessarily consume more fuel than normal A/C mode.
Panel
Outside air flows through the outlets located in the
instrument panel.
Bi-Level
Outside air flows through the outlets located in the
instrument panel and at the floor.
Floor
Outside air flows primarily through the floor out-
lets located under the instrument panel.
Mix
Outside air flows in equal proportions through the
floor and defroster outlets, and the air conditioning
may be on.
Defrost
Outside air is primarily directed to the windshield
through the defroster outlets located at the base of
the windshield, and the demister outlets located at the
edge of each side of the instrument panel, and the air
conditioning may be on.
238 UNDERSTANDING YOUR INSTRUMENT PANEL

Window Fogging
Windows will fog on the inside when the humidity inside
the vehicle is high. This often occurs in mild or cool
temperatures when it’s rainy or humid. In most cases
turning on the Air-conditioning (pressing the snowflake
button) will clear the fog. Adjust the temperature control,
air direction and blower speed to maintain comfort.
As the temperature gets colder it may be necessary to
direct air onto the windshield by using MIX Mode
position on the control. Adjust the temperature control
and blower speed to maintain comfort. Higher blower
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 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.
UNDERSTANDING YOUR INSTRUMENT PANEL 245
4

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.
246 UNDERSTANDING YOUR INSTRUMENT PANEL

STARTING AND OPERATING
CONTENTS

Starting Procedures – Diesel Engines .........253
▫ Manual Transmission – If Equipped ........253
▫ Automatic Transmission – If Equipped ......253
▫ Normal Starting Procedure — Engine Manifold
Airtemperature Above 66°F (19°C) .........254
▫ Starting Procedure — Engine Manifold Air
Temperature Below 66°F (19°C) ...........255
▫ Starting Fluids .......................259

Normal Operation (Diesel Engine) ...........259
▫ Cold Weather Precautions ...............260 ▫
Engine Idling — In Cold Weather ..........263
▫ Stopping The Engine ...................264
▫ Engine Speed Control ..................265
▫ Operating Precautions ..................265
▫ Cooling System Tips —
Automatic Transmission ................266

Transmission Shifting ....................267
▫ Automatic Transmission With Overdrive— If
Equipped ...........................267
5

Block Heater Usage
A.Temperatures below 0°F (-18°C)
•Block Heater Required for 15W-40
•Block Heater Recommended for 5W-40
B. Temperatures below - 20°F (-29°C)
•Block 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 Mopar dealer.
Battery Blanket Usage
A battery loses 60% of its cranking power as the battery
temperature decreases to 0°F (-18°). 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 Mopar dealer.
Arctic Operation
Where there are no provisions to keep the engine warm
when it is operating in ambient temperatures consistently
below (-10°F/-23°C), use 5W-40 syntheticengine oil and
fuel that meets the requirements in Section 7, “Mainte-
nance Procedures,” Engine Oil Selection.
262 STARTING AND OPERATING

Avoid Low Coolant Temperature Operation
Continual operation at low coolant temperature below
the normal range on the gauge (140°F/60°C) 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 — Automatic Transmission
To reduce potential for engine and transmission over-
heating in high ambient temperature conditions, take the
following actions:
•City Driving —
when stopped, put transmission in neutral and increase
engine idle speed.
•Highway Driving —
reduce your speed.
•Up Steep Hills —
select a lower transmission gear, but try and keep the
torque converter locked.
•Air Conditioning —
turn it off temporarily.
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 ............... 10psi(69kPa)
Full speed and load .............. 30psi (207 kPa)
266 STARTING AND OPERATING