308 STARTING AND OPERATING
When to Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting occurs,
push the TOW/HAUL switch to activate TOW/HAUL
mode. This will improve performance and reduce the poten-
tial for transmission overheating or failure due to excessive
shifting.
TOW/HAUL Switch 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.
ACTIVE NOISE CANCELLATION
Your vehicle is equipped with an Active Noise Cancellation
System. This system is designed to address exhaust and
engine noise. The system relies on four microphones
embedded in the headliner, which monitor exhaust and
engine noise, and assists an onboard frequency generator,
which creates counteracting sound waves in the audio
system’s speakers. This helps keep the vehicle quiet at idle
and during drive.
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 possibly resulting in
personal injury or death.
310 STARTING AND OPERATING
(Continued)
4WD LOW
Four-Wheel Drive Low Range — This range provides low
speed four-wheel drive. It maximizes torque (increased
torque over 4WD HIGH) to the front driveshaft; allowing
front and rear wheels to rotate at the same speed. This range
provides additional traction and maximum pulling power
for loose, slippery road surfaces only. Do not exceed 25 mph
(40 km/h) in this range.
NEUTRAL (N)
Neutral — This range disengages both the front and rear
driveshafts from the powertrain. To be used for flat towing
behind another vehicle. Refer to “Recreational Towing” in
this section for further information.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).
Driving the vehicle in 2WD will have greater fuel economy
benefits as the front axle is not engaged in 2WD.
When additional traction is required, the transfer case 4WD
HIGH 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
pushing the desired position on the 4WD control switch.
Refer to “Shifting Procedure” in this section for specific
shifting instructions.
WARNING!
• You or others could be injured or killed if you leave the vehicle unattended with the transfer case in the
NEUTRAL (N) position without first fully engaging
the parking brake. The transfer case NEUTRAL (N)
position disengages both the front and rear drive shaft
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.
• The transmission may not engage PARK if the vehicleis moving. Always bring the vehicle to a complete stop
before shifting to PARK, and verify that the transmis -
sion gear position indicator solidly indicates PARK (P)
without blinking. Ensure that the vehicle is completely
stopped, and the PARK position is properly indicated,
before exiting the vehicle.
WARNING! (Continued)
STARTING AND OPERATING 311
The 4WD HIGH and 4WD LOW positions are designed for
loose, slippery road surfaces only. Driving in the 4WD HIGH
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 button is located in the center of
the 4WD Control Switch and is pushed by using a ballpoint
pen or similar object. The transfer case NEUTRAL position is
to be used for recreational towing only. Refer to “Recre-
ational 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 Of The Following Shift Conditions Are Met:
1. The current position indicator light will turn OFF.
2. The selected position indicator light will flash until the transfer case completes the shift. 3. When the shift is complete, the indicator light for the
selected position will stop flashing and remain ON.
If One Or More Of The Following Shift Conditions Are
Not Met:
1. The indicator light for the current position will remain ON.
2. The newly selected position indicator light will continue to flash.
3. The transfer case will not shift.
NOTE:
Before retrying a selection, make certain that all the neces -
sary requirements for selecting a new transfer case position
have been met. To retry the selection, push the current posi -
tion, wait five seconds, and retry selection. To find the shift
requirements, refer to the "Shifting Procedure" for your
transfer case, located in this section.
The “SVC 4WD Warning Light” monitors the electronic shift
four-wheel drive system. If this light remains on after engine
start up or illuminates during driving, it means that the
four-wheel drive system is not functioning properly and that
service is required.
5
314 STARTING AND OPERATING
Manually Shifted Transfer Case — If Equipped
The transfer case provides four mode positions:
• Two-Wheel Drive High Range (2H)
• Four-Wheel Drive Lock High Range (4H)
• Neutral (N)
• Four-Wheel Drive Low Range (4L)
For additional information on the appropriate use of each
transfer case mode position, see the information below:
2H
Two-Wheel Drive High Range — This range is for normal
street and highway driving on dry, hard surfaced roads.
4H
Four-Wheel Drive Lock 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 both the front and rear
driveshafts from the powertrain. To be used for flat towingbehind another vehicle. Refer to “Recreational Towing” in
“Starting And Operating” for further information.
4L
Four-Wheel Drive Low Range — This range locks the front
and rear driveshafts together forcing the front and rear
wheels to rotate at the same speed. Additional traction and
maximum pulling power for loose, slippery road surfaces
only. Do not exceed 25 mph (40 km/h).
This transfer case is intended to be driven in the 2H position
for normal street and highway conditions such as dry, hard
surfaced roads.
When additional traction is required, the 4H and 4L posi -
tions can be used to lock the front and rear driveshafts
together and force the front and rear wheels to rotate at the
same speed. This is accomplished by simply moving the gear
selector to the desired positions once the appropriate speed
and gear requirements are met, refer to “Shifting Procedure
– Manually Shifted Transfer Case” in this section for further
information.
The 4H and 4L positions are intended for loose, slippery road
surfaces only. Driving in the 4H and 4L positions on dry,
hard surfaced roads may cause increased tire wear and
damage to the driveline components.
316 STARTING AND OPERATING
Neutral (N)
Neutral — This range disengages the front and rear drivesh-
afts from the powertrain. To be used for flat towing behind
another vehicle. Refer to “Recreational Towing” in “Starting
And Operating” for further information.
Four-Wheel Drive Low Range (4L)
Four-Wheel Drive Low Range — This range locks the front
and rear driveshafts together forcing the front and rear
wheels to rotate at the same speed. Additional traction and
maximum pulling power for loose, slippery road surfaces
only. Do not exceed 25 mph (40 km/h).
Shifting Procedure — Manually Shifted Transfer Case
2H To 4H
Shifting between 2H and 4H can be made with the vehicle
stopped or in motion. If the vehicle is in motion, shifts can be
made up to 55 mph (88 km/h). With the vehicle in motion,
the transfer case will engage/disengage 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 To 4L
NOTE:
When shifting into or out of 4L some gear noise may be
heard. This noise is normal and is not detrimental to the
vehicle or occupants.
With the vehicle rolling at 2 to 3 mph (3 to 5 km/h), shift the
transmission into NEUTRAL. 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
NEUTRAL.
NOTE:
• Pausing in transfer case 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 the transmission into NEUTRAL,
hold your foot on the brake, and turn the engine OFF.
Complete the range shift to the desired mode.
• Shifting into or out of 4L is possible with the vehicle completely stopped, however difficulty may occur due to
the mating clutch teeth not being properly aligned. Several
attempts may be required for clutch teeth alignment and
CAUTION!
Do not use 4L (Low) range when operating the vehicle on
dry pavement. Driveline hardware damage can result.
STARTING AND OPERATING 317
shift completion to occur. The preferred 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).
• Do not attempt to shift into or out of 4L while the transmis -
sion is in gear.
Transfer Case Position Indicator Light
The “Transfer Case Position Indicator Light” in the instru-
ment cluster is used to alert the driver that the front axle is
fully engaged and all four wheels are driving.
AIR SUSPENSION SYSTEM (2500/3500 MODELS) — IF
EQUIPPED
Description
This air suspension system is a rear leveling ride height
system. The main purpose of this system is to maintain the
truck’s rear ride height level. There are two selectable heights
that can be chosen based on your operating conditions.
The system requires that the ignition be in ON/RUN posi -
tion or the engine running with zero vehicle speed for all
user requested changes and load leveling. Rear Leveling Ride Height Switch
Normal Ride Height (NRH) – This is the standard position
of the suspension and is meant for normal driving. It will
automatically adjust to maintain the rear ride height as
conditions change.
Alternate Trailer Height (ATH) – Lowers the vehicle
approximately 1 in (25 mm) for a level truck, to be used as
required while trailer towing. It will automatically adjust to
maintain the rear ride height as conditions change.
5
318 STARTING AND OPERATING
Trailer Decoupling/Unloading - The air suspension system
will load level (lower/exhaust only) once after 12 minutes
after the vehicle is turned off. This allows for easy removal of
a trailer and/or load from the back of the truck by main -
taining the ride height. After 12 minutes you will need to
turn the ignition to the run position for the air suspension to
re-level due to addition/removal of load in the vehicle. If the
air suspension system is disabled using the settings menu
(Tire Jack Mode, Transport Mode, Alignment Mode, or Bed
Lowering Mode) the system will remain disabled when the
vehicle is turned off. Reactivating the air suspension can be
accomplished via the settings menu or driving the vehicle
above 5 mph (8 km/h) for Tire Jack Mode or Alignment
Mode and 16 mph (26 km/h) for Transport Mode and Bed
Lowering Mode.
NOTE:
• Most 3500 models will not lower to Alternate Trailer Height (ATH) when unloaded.
• Refer to “Trailer Towing” in “Starting And Operating” for further information. Ignition OFF Behavior
For a predetermined amount of time after the ignition is off the
air suspension may adjust to maintain a proper appearance.
Air Suspension Modes
The air suspension system has multiple modes to protect the
system in unique situations:
Tire/Jack Mode
To assist with changing a tire, the air suspension system has a
feature which allows the automatic leveling to be disabled. This
mode is intended to be enabled with engine running. Refer to
“Instrument Cluster Display” in “Getting To Know Your Instru
-
ment Panel” or “Uconnect Settings” in “Multimedia” if equipped
with a touch screen radio for further information.
NOTE:
This mode is intended to be enabled with engine running.
WARNING!
The air suspension system uses a high pressure volume
of air to operate the system. To avoid personal injury or
damage to the system, see your authorized dealer for
service.
STARTING AND OPERATING 319
Transport Mode
For towing your vehicle with four wheels off the road, the air
suspension system has a feature which will put the vehicle
below Normal Ride Height (NRH) and disable the automatic
load leveling system. This mode is intended to be enabled
with engine running. Refer to “Instrument Cluster Display”
in “Getting To Know Your Instrument Panel” or “Uconnect
Settings” in “Understanding Your Instrument Panel” if
equipped with a touch screen radio for further information.
NOTE:
This mode is intended to be enabled with engine running.
Wheel Alignment Mode
Before performing a wheel alignment this mode must be
enabled. Refer to “Instrument Cluster Display” in “Getting
To Know Your Instrument Panel” or “Uconnect Settings” in
“Multimedia” if equipped with a touch screen radio for
further information.
NOTE:
This mode is intended to be enabled with engine running.Bed Lowering Mode
For towing your vehicle with four wheels off the road, the air
suspension system has a feature which will put the vehicle
below Normal Ride Height (NRH) and disable the automatic
load leveling system. This mode is intended to be enabled
with engine running. Refer to “Instrument Cluster Display”
in “Getting To Know Your Instrument Panel” or “Uconnect
Settings” in “Understanding Your Instrument Panel” if
equipped with a touch screen radio for further information.
Protection Strategy
In order to “protect” the air suspension system, the vehicle
will disable load leveling as required (suspension over
-
loaded, battery charge low, etc.). Load leveling will automat -
ically resume as soon as system operation requirements are
met. See your authorized dealer if system does not resume.
5