2007 Ram 2500 (Diesel) automatic transmission

•engine running
•foot off the brake pedal
•driver ’s seat belt is unbuckled
•driver ’s door is open.
When this feature is triggered the horn will sound, the
high beams and turn signal lamps will flash, and the
PRNDL position will flash. This will continue until one of
the following conditions is met:
•engine is turned off
•transmission is in Park
•driver ’s seat belt is buckled
•brakes applied.The alarm will continue for 3 minutes if the driver’s door
is closed but none of the other conditions listed above are
met.
Automatic Transmission with Overdrive (48RE) —
If Equipped
The gear shift selector display, located in the instrument
panel cluster, indicates the transmission gear range (the
selector is illuminated for night driving). The selector
lever is mounted on the right side of the steering column.
You must depress the brake pedal, to pull the selector
lever out of park (P) position (Brake Interlock System). To
drive, move the selector lever from Park or Neutral to the
desired drive position. Pull the selector lever toward you
when shifting into Reverse, Second, First or Park, or
when shifting out of Park.
Gear Ranges
DO NOT race the engine when shifting from Park or
Neutral position into another gear range.
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5

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).
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When To Use “TOW HAUL” and “O/D OFF”
Modes
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, press the “TOW HAUL O/D OFF” button once to
select TOW HAUL. This will improve performance andreduce the potential for transmission overheating or
failure due to excessive shifting. When operating in
“TOW HAUL” mode, 5th gear (if equipped) is disabled
and 2-3 and 3-4 shift patterns are modified. Shifts into
Overdrive (4th gear) are allowed during steady cruise
(for improved fuel economy) and automatic closed-
throttle downshifts to 3rd gear (for improved braking)
will occur during steady braking. Pressing the “TOW
HAUL O/D OFF” button a second time to select O/D
OFF will disable 4th and 5th gear completely, which
should eliminate any excessive transmission shifting.
The “TOW HAUL” or “O/D OFF” light will illuminate in
the instrument cluster to indicate when the switch has
been activated. Pressing the switch a third time restores
normal operation. If the “TOW HAUL” or “O/D OFF”
modes are desired, the button must be pressed each time
the engine is started.
Tow Haul O/D Off Switch
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5

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
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vehicle in motion, the transfer case will engage / disen-
gage faster if you momentarily release the accelerator
pedal after completing the shift. Apply a constant force
when shifting the transfer case lever.
2H or 4H⇔4L
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift
an automatic transmission to N (Neutral) or depress the
clutch on a manual transmission. While the vehicle is
coasting at 2 to 3 mph (3 to 5 km/h), shift the transfer
case lever firmly to the desired position. Do not pause in
transfer case N (Neutral).
NOTE:Pausing in transfer case N (Neutral) in vehicles
equipped with an automatic transmission may require
shutting the engine OFF to avoid gear clash while
completing the shift. If difficulty occurs, shift automatic
transmission to N (Neutral), hold foot on brake, and turn
engine OFF. Make shift to the desired mode.NOTE:Shifting into or out of 4L is possible with the
vehicle completely stopped, however difficulty may oc-
cur due to the mating clutch teeth not being properly
aligned. Several attempts may be required for clutch
teeth alignment and shift completion to occur. The pre-
ferred method is with the vehicle rolling 2 to 3 mph (3 to
5 km/h). Avoid attempting to engage or disengage 4L
with the vehicle moving faster than 2 to 3 mph (3 to 5
km/h).
NOTE:Do not attempt to shift to or from 4L while the
transmission is in gear or clutch is engaged.
Transfer Case Reminder Light
The four-wheel-drive operating light (4WD), located in
the instrument cluster, is used to alert the driver that the
front axle is fully engaged and all four wheels are
driving.
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5

WARNING!
•Always fully apply the parking brake when leav-
ing your vehicle, or it may roll and cause damage
or injury. Also be certain to leave an automatic
transmission in Park, a manual transmission in
Reverse or First gear. Failure to do so may allow
the vehicle to roll and cause damage or injury.
•Never leave children alone in a vehicle. Leaving
children in a vehicle unattended is dangerous for a
number of reasons. A child or others could be
seriously or fatally injured. Don’t leave the keys in
the ignition. A child could operate power win-
dows, other controls, or move the vehicle.
•Be sure the parking brake is fully disengaged
before driving, failure to do so can lead to brake
problems due to excessive heating of the rear
brakes.When parking on a hill, turn the front wheels toward the
curb on a downhill grade and away from the curb on an
uphill grade.
The parking brake should always be applied whenever
the driver is not in the vehicle.
BRAKE SYSTEM
If power assist is lost for any reason (for example,
repeated brake applications with the engine off), the
brakes will still function. However, you will experience a
substantial increase in braking effort to stop the vehicle.
If either the front or rear hydraulic systems lose normal
capability, the remaining system will still function with
some loss of overall braking effectiveness. This will be
evident by increased pedal travel during application,
greater pedal force required to slow or stop, and activa-
tion of the BRAKE warning lamp and the ABS lamp (if
equipped) during brake use.
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Perform the maintenance listed in Section 8 of this
manual. When towing a trailer, never exceed the GAWR,
or GCWR, ratings.
WARNING!
Improper towing can lead to an injury accident.
Follow these guidelines to make your trailer towing
as safe as possible:
Make certain that the load is secured in the trailer
and will not shift during travel. When trailering
cargo that is not fully secured, dynamic load shifts
can occur that may be difficult for the driver to
control. You could lose control of your vehicle and
have an accident.
•When hauling cargo or towing a trailer, do not over-
load your vehicle or trailer. Overloading can cause aloss of control, poor performance or damage to brakes,
axle, engine, transmission, steering, suspension, chas-
sis structure or tires.
•Safety chains must always be used between your
vehicle and trailer. Always connect the chains to the
frame or hook retainers of the vehicle hitch. Cross the
chains under the trailer tongue and allow enough
slack for turning corners.
•Vehicles with trailers should not be parked on a grade.
When parking, apply the parking brake on the tow
vehicle. Put the tow vehicle automatic transmission in
P for Park. With a manual transmission, shift the
transmission into reverse. And with four-wheel-drive
vehicles, make sure the transfer case is not in neutral.
Always, block orchockthe trailer wheels.
•GCWR must not be exceeded.
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5

Towing Tips
Before setting out on a trip, practice turning, stopping
and backing the trailer in an area away from heavy
traffic.
If using a manual transmission vehicle for trailer towing,
all starts must be in FIRST gear to avoid excessive clutch
slippage.
Towing Tips — Automatic Transmission
The “D” range can be selected when towing. However, if
frequent shifting occurs while in this range, the “TOW
HAUL” or “OD/OFF” range should be selected.
NOTE:Using the “TOW HAUL” or “OD/OFF” range
while operating the vehicle under heavy operating con-
ditions will improve performance and extend transmis-
sion life by reducing excessive shifting and heat build up.
This action will also provide better engine braking.The automatic transmission fluid and filter should be
changed if you REGULARLY tow a trailer for more than
45 minutes of continuous operation. See Schedule “B” in
section 8 of this manual for transmission fluid change
intervals.
NOTE:Check the automatic transmission fluid level
before towing.
Towing Tips — Tow/Haul (If Equipped)
To reduce potential for automatic transmission overheat-
ing, turn the “TOW HAUL OD/OFF” feature ON when
driving in hilly areas or shift the transmission to Drive
position 2 on more severe grades.
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