2007 Ram 2500 (Diesel) automatic transmission fluid

23. 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.
24. 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. (See page 427 for more information.)
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 mayalso 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 66 degrees F.
Follow engine starting procedure for proper engine start-
ing and operating. Wait until the Wait To Start Indicator
turns OFF then start the vehicle.
NOTE:The Wait To Start Indicator may not illuminate if
the engine coolant temperature is warm enough.
UNDERSTANDING YOUR INSTRUMENT PANEL 205
4

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.
268 UNDERSTANDING YOUR INSTRUMENT PANEL

STARTING AND OPERATING
CONTENTS

Starting Procedures – Diesel Engines.........275
▫Manual Transmission – If Equipped........275
▫Automatic Transmission – If Equipped......276
▫Normal Starting Procedure — Engine Manifold
Airtemperature Above 66°F (19°C).........276
▫Starting Procedure — Engine Manifold Air
Temperature Below 66°F (19°C)...........277
▫Starting Fluids.......................281

Normal Operation (Diesel Engine)...........281▫Cold Weather Precautions...............282
▫Engine Idling — In Cold Weather..........286
▫Stopping The Engine...................287
▫Engine Speed Control..................288
▫Operating Precautions..................288
▫Cooling System Tips —
Automatic Transmission................288

Diesel Exhaust Brake (Engine Braking) –
If Equipped...........................290
5

Upshifts into both overdrive gears, 5th and 6th, will be
delayed when the transmission fluid temperature is
below 40° F (4.5° C) or above 240° F (115.5° C).
NOTE:Use caution when operating a heavily loaded
vehicle in 2nd or 1st First gear 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 overdrive automatic transmission contains an elec-
tronically controlled 5th and 6th (Overdrive). The trans-
mission 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;
•vehicle speed is above approximately 30 mph (48
km/h);
•the “TOW HAUL” switch has not been activated;
•transmission has reached normal operating tempera-
ture.
STARTING AND OPERATING 293
5

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 level. 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 TRANS TEMP light
may illuminate. After cool down, the transmission will
resume normal operation.
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).When To Use “TOW HAUL”
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the “TOW HAUL button once to select TOW
HAUL. In TOW HAUL mode, 4th to 5th gear upshifts are
1 — Tow/Haul Switch
2 — AUTO-6 (ERS) Switch 294 STARTING AND OPERATING

NOTE:To select the proper gear position for maximum
deceleration (engine braking), simply press and hold the
switch down (-). The transmission will shift to the range
from which the vehicle can best be slowed down.
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 transmissionis not shifting into Overdrive when cold. This is normal.
Pressing the “TOW/HAUL” 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.
Out of Park Sense Alarm — If Equipped
Vehicles equipped with a Diesel Engine and a Automatic
Transmission may be equipped with an Alarm that warns
the customer, upon exiting the vehicle, that the transmis-
sion is not in the Park position. This feature will only be
functional under following conditions:
296 STARTING AND OPERATING

Overdrive Operation
The overdrive automatic transmission contains an elec-
tronically controlled fourth and fifth (if equipped) 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;
•vehicle speed is above approximately 30 mph (48
km/h);
•the “TOW HAUL O/D OFF” switch has not been
activated;
•transmission has reached normal operating tempera-
ture.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 level. 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 TRANS TEMP light
may illuminate and the transmission may downshift out
of Overdrive until the transmission cools down. After
cooldown, the transmission will resume normal opera-
tion.
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).
300 STARTING AND OPERATING

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
occurs, press the “TOW/HAUL” 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]. Becausethe 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 “TOW/HAUL” 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.
Out of Park Sense Alarm
Vehicles with a Diesel Engine and an Automatic Trans-
mission are equipped with an Alarm that warns the
302 STARTING AND OPERATING