2007 RAM CHASSIS CAB cooling

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. (See page 398 for more
information.)
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 283 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 271 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 271 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.”174 UNDERSTANDING YOUR INSTRUMENT PANEL

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. UNDERSTANDING YOUR INSTRUMENT PANEL 175
4

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.234 UNDERSTANDING YOUR INSTRUMENT PANEL

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.
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 241
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▫ Operating Precautions ..................263
▫ Cooling System Tips — Automatic Transmission 263

Engine Block Heater — If Equipped .........265

Diesel Exhaust Brake (Engine Braking) – If
Equipped ............................265

Automatic Transmission ..................266
▫ Automatic Transmission With Overdrive (5 Speed
545RFE) — If Equipped .................267
▫ Automatic Transmission (6 Speed AS68RC) — If
Equipped ...........................273

Manual Transmission ....................279
▫ Manual Transmission — 6 Speed (G56) ......280
▫ Recommended Vehicle Shift Speeds ........280
▫ Downshifting – Gas Engine ..............281 ▫ Downshifting – Diesel Engine ............282

Four-Wheel- Drive Operation — If Equipped . . . 283
▫ Manually Shifted Transfer Case Operating
Information/Precautions ................283
▫ Shifting Procedure - Manually Shifted Transfer
Case ..............................286
▫ Transfer Case Reminder Light ............287
▫ Electronically Shifted Transfer Case Operating
Information/Precautions (4 Position Switch)—If
Equipped ...........................288
▫ Shifting Procedure - Electronically Shifted Transfer
Case ..............................292

Limited-Slip Differential — If Equipped .......295

Power Take Off Operation – If Equipped ......296
▫ Stationary Mode ......................296244 STARTING AND OPERATING

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 synthetic engine oil and
fuel that meets the requirements in Section 7, “Mainte-
nance Procedures,” 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.260 STARTING AND OPERATING

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 (240°F/116°C)
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 (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. STARTING AND OPERATING 263
5

“N” Neutral
Shift to Neutral when the vehicle is standing for pro-
longed periods with the engine running. The engine may
be started in this range. Set the parking brake if you must
leave the vehicle.
“D” Drive
This position provides all forward gears, including 3rd
gear direct and 4th or 5th gear overdrive (see Overdrive
Operation). Use this range for most city and highway
driving.
“2” Second
Use this position for driving slowly in heavy city traffic
or on mountain roads where more precise speed control
is desirable. Use it also when climbing long grades, and
for engine braking when descending moderately steep
grades. To prevent excessive engine speed do not exceed
45 mph (72 km/h) in this range. “1” 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 “2” Second or “1” First gear selections in high
ambients as torque converter slip can impose significant
additional heat load on the cooling system.
Overdrive Operation
The overdrive automatic transmission contains an elec-
tronically controlled fourth and fifth speed (Overdrive).
The transmission will automatically shift from Drive to
Overdrive if the following conditions are present:
• the transmission selector is in Drive;
• the engine coolant has reached normal operating tem-
perature; STARTING AND OPERATING 269
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