tow Ram 3500 2015 Repair Manual

The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode has
been activated. Pushing the switch a second time restores
normal operation. Normal operation is always the default
at engine start-up. If TOW/HAUL mode is desired, the
switch must be pushed each time the engine is started.
WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. 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.
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
the upper gears. When the vehicle speed drops or during
some accelerations, the clutch automatically disengages.
TOW/HAUL Switch
5
STARTING AND OPERATING 475

NOTE:
•The torque converter clutch will not engage, and the
transmission will not shift into the top overdrive gear,
until the transmission fluid and engine coolant are
warm [usually after 1 to 3 miles (2 to 5 km) of driving].
Because top gear is disabled, and the engine speed is
higher when the torque converter clutch is not en-
gaged, it may seem as if the transmission is not shifting
properly when cold. This is normal. Using the Elec-
tronic Range Select (ERS) shift control, when the
transmission is sufficiently warm, will demonstrate
that the transmission is able to shift into and out of
Overdrive.
• If the vehicle has not been driven for several days, the
first few seconds of operation after shifting the trans-
mission 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 con-
verter will refill within five seconds after starting the
engine.
Six-Speed Automatic Transmission — 2500/3500
Models Only
The transmission gear position display (located in the
instrument cluster) indicates the transmission gear range.
The shift lever is mounted on the right side of the steering
column. You must press the brake pedal to move the shift
lever out of PARK (refer to “Brake/Transmission Shift
Interlock System” in this section for further information).
To drive, move the shift lever from PARK or NEUTRAL
to the DRIVE position. Pull the shift lever toward you
when shifting into REVERSE or PARK, or when shifting
out of PARK.
The electronically-controlled transmission provides a
precise shift schedule. The transmission electronics are
self-calibrating; therefore, the first few shifts on a new
476 STARTING AND OPERATING

When parking on a hill, apply the parking brake before
shifting the transmission to PARK, otherwise the load on
the transmission locking mechanism may make it diffi-
cult to move the shift lever out of PARK. As an added
precaution, turn the front wheels toward the curb on a
downhill grade and away from the curb on an uphill
grade.
On four-wheel drive vehicles be sure that the transfer
case is in a drive position.
WARNING!
•Never use the PARK position as a substitute for the
parking brake. Always apply the parking brake
fully when parked to guard against vehicle move-
ment and possible injury or damage.
• Your vehicle could move and injure you and others
if it is not completely in PARK. Check by trying to
(Continued)
WARNING! (Continued)
move the shift lever out of PARK with the brake
pedal released. Make sure the transmission is in
PARK before leaving the vehicle.
• It is dangerous to shift out of PARK or NEUTRAL
if the engine speed is higher than idle speed. If
your foot is not firmly pressing the brake pedal, the
vehicle could accelerate quickly forward or in re-
verse. You could lose control of the vehicle and hit
someone or something. Only shift into gear when
the engine is idling normally and your foot is
firmly pressing the brake pedal.
• Unintended movement of a vehicle could injure
those in or near the vehicle. As with all vehicles,
you should never exit a vehicle while the engine is
running. Before exiting a vehicle, always apply the
parking brake, shift the transmission into PARK,
(Continued)
478 STARTING AND OPERATING

The following indicators should be used to ensure that
you have engaged the transmission into the PARK posi-
tion:
•When shifting into PARK, pull the shift lever toward
you and move it all the way counterclockwise until it
stops.
• Release the shift lever and make sure it is fully seated
in the PARK gate.
• Look at the transmission gear position display and
verify that it indicates the PARK position (P).
• With brake pedal released, verify that the shift lever
will not move out of PARK.
REVERSE (R)
This range is for moving the vehicle backward. Shift into
REVERSE only after the vehicle has come to a complete
stop. NEUTRAL (N)
Use this range when the vehicle is standing for prolonged
periods with the engine running. The engine may be
started in this range. Apply the parking brake and shift
the transmission into PARK if you must leave the vehicle.
WARNING!
Do not coast in NEUTRAL and never turn off the
ignition to coast down a hill. These are unsafe
practices that limit your response to changing traffic
or road conditions. You might lose control of the
vehicle and have a collision.
480 STARTING AND OPERATING

CAUTION!
Towing the vehicle, coasting, or driving for any other
reason with the transmission in NEUTRAL can cause
severe transmission damage. Refer to “Recreational
Towing” in “Starting And Operating” and “Towing A
Disabled Vehicle” in “What To Do In Emergencies”
for further information.
DRIVE (D)
This range should be used for most city and highway
driving. It provides the smoothest upshifts and down-
shifts, and the best fuel economy. The transmission
automatically upshifts through underdrive first, second,
and third gears, direct fourth gear and overdrive fifth and
sixth gears. The DRIVE position provides optimum driv-
ing characteristics under all normal operating conditions.
When frequent transmission shifting occurs (such as when
operating the vehicle under heavy loading conditions, in
hilly terrain, traveling into strong head winds, or while
towing heavy trailers), use the Electronic Range Select
(ERS) shift control (refer to “Electronic Range Select (ERS)
Operation” in this section for further information) to select
a lower gear range. Under these conditions, using a lower
gear range will improve performance and extend transmis-
sion life by reducing excessive shifting and heat buildup.
If the transmission temperature exceeds normal operat-
ing limits, the powertrain controller will modify the
transmission shift schedule and expand the range of
torque converter clutch engagement. This is done to
prevent transmission damage due to overheating.
If the transmission becomes extremely hot or is in danger
of overheating, the “Transmission Temperature Warning
Light” may illuminate and the transmission may operate
differently until the transmission cools down.
5
STARTING AND OPERATING 481

NOTE:Use caution when operating a heavily loaded
vehicle at low speeds (such as towing a trailer up a steep
grade, or in stop-and-go traffic) during hot weather. In
these conditions, torque converter slip can impose a
significant additional heat load on the cooling system.
Downshifting the transmission to the lowest possible
gear (when climbing a grade), or shifting to NEUTRAL
(when stopped in heavy traffic) can help to reduce this
excess heat generation.
During cold temperatures, transmission operation may
be modified depending on engine and transmission
temperature as well as vehicle speed. This feature im-
proves warm up time of the engine and transmission to
achieve maximum efficiency. Engagement of both the
torque converter clutch and the top overdrive gear are
inhibited until the transmission fluid is warm (refer to the
“Note” under “Torque Converter Clutch” in this section).
During extremely cold temperatures (-16°F [-27°C] or
below), operation may briefly be limited to first and direct gears only. Normal operation will resume once the
transmission temperature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electronically for
abnormal conditions. If a condition is detected that could
result in transmission damage, Transmission Limp Home
Mode is activated. In this mode, the transmission remains
in fourth gear regardless of which forward gear is
selected. PARK, REVERSE, and NEUTRAL will continue
to operate. The Malfunction Indicator Light (MIL) may be
illuminated. Limp Home Mode allows the vehicle to be
driven to an authorized dealer for service without dam-
aging the transmission.
In the event of a momentary problem, the transmission
can be reset to regain all forward gears by performing the
following steps:
1. Stop the vehicle.
482 STARTING AND OPERATING

Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (fifth and sixth gears). The trans-
mission will automatically shift into Overdrive if the
following conditions are present:
•The shift lever is in the DRIVE position.
• The transmission fluid has reached an adequate tem-
perature.
• The engine coolant has reached an adequate tempera-
ture.
• Vehicle speed is sufficiently high.
• The TOW/HAUL switch has not been activated.
• The driver is not heavily pressing the accelerator.
When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting oc-
curs, push the TOW/HAUL switch to activate TOW/
HAUL mode. This will improve performance and reduce
the potential for transmission overheating or failure due
to excessive shifting. When operating in TOW/HAUL
mode, transmission upshifts are delayed, and the trans-
mission will automatically downshift (for engine brak-
ing) during steady braking maneuvers.
5
STARTING AND OPERATING 485

The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode
has been activated. Pushing the switch a second time
restores normal operation. Normal operation is always
the default at engine start-up. If TOW/HAUL mode isdesired, the switch must be pushed each time the engine
is started.
WARNING!
Do not use the “TOW/HAUL” feature when driving
in icy or slippery conditions. 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.
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
TOW/HAUL Switch
486 STARTING AND OPERATING

Because four-wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
NOTE:Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or uneven tire
pressures, excessive vehicle loading, or cold tempera-
tures.
WARNING!
You or others could be injured or killed if you leave
the vehicle unattended with the transfer case in the
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
disengages both the front and rear drive shafts from
the powertrain and will allow the vehicle to roll,
even if the transmission is in PARK. The parking
brake should always be applied when the driver is
not in the vehicle. For additional information on the appropriate use of each
transfer case mode position, see the information below:
2H
Rear-Wheel Drive High Range — This range is for
normal street and highway driving on dry hard surfaced
roads.
4H
Four-Wheel Drive High Range — This range locks the
front and rear driveshafts together forcing the front and
rear wheels to rotate at the same speed. Additional
traction for loose, slippery road surfaces only.
Neutral (N)
Neutral — This range disengages the front and rear
driveshafts from the powertrain. To be used for flat
towing behind another vehicle. Refer to “Recreational
Towing” in “Starting And Operating” for further infor-
mation.
5
STARTING AND OPERATING 489

This electronically shifted transfer case provides four
mode positions:
•Two-wheel drive high range (2WD)
• Four-wheel drive lock range (4WD LOCK)
• Four-wheel drive low range (4WD LOW)
• Neutral (NEUTRAL)
This electronically shifted transfer case is designed to be
driven in the two-wheel drive position (2WD) for normal
street and highway conditions on dry, hard surfaced roads.
When additional traction is required, the transfer case 4WD
LOCK and 4WD LOW positions can be used to maximize
torque to the front driveshaft, forcing the front and rear
wheels to rotate at the same speed. This is accomplished by
rotating the 4WD Control Switch to the desired position.
Refer to “Shifting Procedure” in this section for specific
shifting instructions. The 4WD LOCK and 4WD LOW
positions are designed for loose, slippery road surfaces only. Driving in the 4WD LOCK and 4WD LOW positions
on dry hard surfaced roads may cause increased tire wear
and damage to the driveline components.
NOTE:
The transfer case NEUTRAL position is selected
by pushing the button located on the lower left hand
corner of the 4WD Control Switch. The transfer case
NEUTRAL position is to be used for recreational towing
only. Refer to “Recreational Towing” in “Starting And
Operating” for further information.
Transfer Case Position Indicator Lights
The Transfer Case Position Indicator Lights (4WD and
4LOW) are located in the instrument cluster and indicate
the current and desired transfer case selection. When you
select a different transfer case position, the indicator
lights will do the following:
If All Shift Conditions Are Met:
1. The current position indicator light will turn OFF.
492 STARTING AND OPERATING