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
322 STARTING AND OPERATING
To lock the rear axle, place the vehicle in 4LO. Refer to “Four
Wheel Drive Operation” in “Starting And Operating” for
further information. Push the REAR LOCK button while
traveling less than 3 mph (5 km/h). The RR indicator light
will remain on when the rear axle is locked.
NOTE:
Left to right wheel speed difference may be necessary to
allow the axle to fully lock. If the indicator light is flashing
after placing the switch in the REAR LOCK or FRONT/
REAR LOCK position, drive the vehicle in a turn or on loose
gravel to expedite the locking action.
To lock the front axle; push the FRONT/REAR LOCK button
while traveling less than 3 mph (5 km/h). The indicator light
will be solid when the front axle is locked.
NOTE:
The rear axle must be locked before the front axle will lock. To unlock the front axle; push the REAR LOCK button. The
FRONT/REAR LOCK indicator light will go out when the
axle is unlocked.
NOTE:
The axle lockers could be torque locked due to side to side
loads on the axle. Driving slowly while turning the steering
wheel from a left hand turn to a right hand turn or driving in
REVERSE for a short distance may be required to release the
torque lock and unlock the axles.
To unlock the rear axle; push the AXLE UNLOCK button.
The REAR LOCK indicator light will go out when the rear
axle is unlocked.
STABILIZER/SWAY BAR SYSTEM — POWER WAGON
ONLY
Your vehicle is equipped with an electronic disconnecting
stabilizer/sway bar. This system allows greater front
suspension travel in off-road situations.
Due to the use of taller springs, this vehicle has an increased
ride height of approximately 1.9 in (48.3 mm) in the front
and 1.5 in (38.1 mm) in the rear. A major advantage to
increasing ride height is the positive effect it has on
approach/departure and break over angles.
WARNING!
Do not use the locked axle position for normal driving. A
locked front axle is intended for off-road driving only.
Locking the front axle during on-road driving will
reduce the steering ability. This could cause a collision
and you may be seriously injured.
STARTING AND OPERATING 323
This system is controlled by the electronic control sway bar
switch located below the instrument panel.Sway Bar Disconnect Button
Push the SWAY BAR switch to activate the system. Push the
switch again to deactivate the system. The “Sway Bar Indi -
cator Light” (located in the instrument cluster) will illumi -
nate when the bar is disconnected. The “Sway Bar Indicator
Light” will flash during activation transition, or when activa -
tion conditions are not met. The stabilizer/sway bar should
remain in on-road mode during normal driving conditions. To disconnect the stabilizer/sway bar, shift to either 4HI or
4LO and push the SWAY BAR button to obtain the Off-Road
position. Refer to “Four Wheel Drive Operation” in “Starting
And Operating” for further information. The “Sway Bar
Indicator Light” will flash until the stabilizer/sway bar has
been fully disconnected.
NOTE:
The stabilizer/sway bar may be torque locked due to left and
right suspension height differences. This condition is due to
driving surface differences or vehicle loading. In order for
the Stabilizer/Sway Bar to disconnect/reconnect, the rightWARNING!
Do not disconnect the stabilizer bar and drive on hard
surfaced roads or at speeds above 18 mph (29 km/h), you
may lose control of the vehicle, which could result in
serious injury or death. The front stabilizer bar enhances
vehicle stability and assists in maintaining control of the
vehicle. The system monitors vehicle speed and will
attempt to reconnect the stabilizer bar at speeds over
18 mph (29 km/h). This is indicated by a flashing off road
light and solid on road light. Once vehicle speed is
reduced below 14 mph (22 km/h), the system will
attempt to return to the Off-Road mode.
5
336 STARTING AND OPERATING
After Driving Off-Road
Off-road operation puts more stress on your vehicle than
does most on-road driving. After going off-road, it is always
a good idea to check for damage. That way you can get any
problems taken care of right away and have your vehicle
ready when you need it.
• Completely inspect the underbody of your vehicle. Checktires, body structure, steering, suspension, and exhaust
system for damage.
• Inspect the radiator for mud and debris and clean as required.
• Check threaded fasteners for looseness, particularly on the chassis, drivetrain components, steering, and suspension.
Retighten them, if required, and torque to the values spec -
ified in the Service Manual.
• Check for accumulations of plants or brush. These things could be a fire hazard. They might hide damage to fuel
lines, brake hoses, axle pinion seals, and propeller shafts. • After extended operation in mud, sand, water, or similar
dirty conditions, have the radiator, fan, brake rotors,
wheels, brake linings, and axle yokes inspected and
cleaned as soon as possible.
• If you experience unusual vibration after driving in mud, slush or similar conditions, check the wheels for impacted
material. Impacted material can cause a wheel imbalance
and freeing the wheels of it will correct the situation.
WARNING!
Abrasive material in any part of the brakes may cause
excessive wear or unpredictable braking. You might not
have full braking power when you need it to prevent a
collision. If you have been operating your vehicle in
dirty conditions, get your brakes checked and cleaned as
necessary.
STARTING AND OPERATING 359
Adaptive Cruise Control (ACC) Operation
The speed control buttons (located on the right side of the
steering wheel) operate the ACC system.Adaptive Cruise Control Buttons
NOTE:
Any chassis/suspension or tire size modifications to the
vehicle will effect the performance of the Adaptive Cruise
Control and Forward Collision Warning System.
• Will bring the vehicle to a complete stop while
following a target vehicle and hold the vehicle for
approximately two seconds in the stop position. At
this point, there will be an “ACC may cancel soon”
chime and warning to the driver. When ACC is
cancelled, the system will release the brakes and the
driver must take over braking. The system can be
resumed when the target vehicle drives off by
releasing the brake and pushing the resume button
on the steering wheel.
You should switch off the ACC system:
• When driving in fog, heavy rain, heavy snow, sleet, heavy traffic, and complex driving situations (i.e., in
highway construction zones).
• When entering a turn lane or highway off ramp; when driving on roads that are winding, icy, snow-covered,
slippery, or have steep uphill or downhill slopes.
• When towing a trailer up or down steep slopes.
• When circumstances do not allow safe driving at a constant speed.
WARNING! (Continued)
1 — Adaptive Cruise Control On/Off Button
2 — Distance Button
5
410 STARTING AND OPERATING
Loose Fuel Filler Cap Message
If the vehicle diagnostic system determines that the
fuel filler cap is loose, improperly installed, or
damaged, a loose gascap indicator will display in the
instrument cluster telltale display area. Refer to “Instrument
Cluster Display” in “Getting To Know Your Instrument
Panel” for further information. Tighten the fuel filler cap
properly and push the RIGHT button to turn off the message.
If the problem continues, the message will appear the next
time the vehicle is started.
VEHICLE LOADING
Gross Vehicle Weight Rating (GVWR)
The GVWR is the total permissible weight of your vehicle
including driver, passengers, vehicle, options and cargo. The
label also specifies maximum capacities of front and rear axle
systems (GAWR). Total load must be limited so GVWR and
front and rear GAWR are not exceeded.
Payload
The payload of a vehicle is defined as the allowable load
weight a truck can carry, including the weight of the driver,
all passengers, options and cargo.
Gross Axle Weight Rating (GAWR)
The GAWR is the maximum permissible load on the front
and rear axles. The load must be distributed in the cargo area
so that the GAWR of each axle is not exceeded.
Each axle GAWR is determined by the components in the
system with the lowest load carrying capacity (axle, springs,
tires or wheels). Heavier axles or suspension components
sometimes specified by purchasers for increased durability
does not necessarily increase the vehicle's GVWR.
Tire Size
The tire size on the Vehicle Certification Label represents the
actual tire size on your vehicle. Replacement tires must be
equal to the load capacity of this tire size.
Rim Size
This is the rim size that is appropriate for the tire size listed.
Inflation Pressure
This is the cold tire inflation pressure for your vehicle for all
loading conditions up to full GAWR.
STARTING AND OPERATING 415
Improper Adjustment Of Weight-Distributing Hitch (Incorrect)
Recommended Distribution Hitch Adjustment
Towing With 2500/3500 Air Suspension
1. Position the truck to be ready to connect to the trailer (do not connect the trailer). NOTE:
Normal Ride Height (NRH) or Alternate Trailer Height
(ATH) can be used. The vehicle must remain in the engine
running position while attaching a trailer for proper leveling
of the air suspension system. It may not be possible to enter
Alternate Trailer Height (ATH) while lightly loaded.
2. Measure the height of the top of the front wheel opening
on the fender to ground, this is height H1.
3. Attach the trailer to the vehicle without the weight distri -
bution bars connected.
4. Measure the height of the top of the front wheel opening on the fender to ground, this is height H2.
5. Install and adjust the tension in the weight distributing bars per the manufacturers’ recommendations so that the
height of the front fender is approximately (H2-H1)/
2+H1 (about 1/2 the difference between H2 and H1 above
normal ride height [H1]).
5
416 STARTING AND OPERATING
6. Perform a visual inspection of the trailer and weightdistributing hitch to confirm manufacturers’ recommen -
dations have been met.
NOTE:
For all towing conditions, we recommend towing with tow
haul mode engaged.
Towing With All Other 2500/3500 (Non-Air Suspension)
1. Position the truck to be ready to connect to the trailer (do not connect the trailer).
2. Measure the height of the top of the front wheel opening on the fender to ground, this is height H1.
3. Attach the trailer to the vehicle without the weight distri -
bution bars connected. 4. Measure the height of the top of the front wheel opening
on the fender to ground, this is height H2.
5. Install and adjust the tension in the weight distributing bars per the manufacturers’ recommendations so that the
height of the front fender is approximately (H2-H1)/
2+H1 (about 1/2 the difference between H2 and H1 above
normal ride height [H1]).
6. Perform a visual inspection of the trailer and weight distributing hitch to confirm manufacturers’ recommen -
dations have been met.
NOTE:
For all towing conditions, we recommend towing with tow
haul mode engaged.
Measurement Example
Example 2500/3500
Height (mm)
H1 1030
H2 1058
H2-H1 28
(H2-H1)/2 14
(H2-H1)/2 + H1 1044
Measurement ExampleExample 2500/3500
Height (mm)
H1 1030
H2 1058
H2-H1 28
(H2-H1)/2 14
(H2-H1)/2 + H1 1044