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 condi-
tions.
The system requires that the ignition be in ON/RUN
position or the engine running with zero vehicle speed for
all user requested changes and load leveling.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.
Trailer Decoupling/Unloading - The air suspension sys-
tem will load level (lower/exhaust only) for up to 10
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 maintaining the ride height. After 10 minutes you will
need to turn the ignition to the run position for the air
suspension to maintain ride height. If the air suspension
system is disabled using the settings menu (Tire Jack Mode,
Transport Mode or Alignment Mode) the system will
remain disabled when the vehicle is turned off. Reactivat-
ing 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.
Rear Leveling Ride Height Switch
356 STARTING AND OPERATING
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 appear-
ance.
WARNING!
The air suspension system uses a high pressure vol-
ume of air to operate the system. To avoid personal
injury or damage to the system, see your authorized
dealer for service.
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 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.
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
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STARTING AND OPERATING 357
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.
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 auto-
matically resume as soon as system operation requirements
are met. See your authorized dealer if system does not
resume.
Instrument Cluster Display Messages
When the appropriate conditions exist, a message will
appear in the instrument cluster display. Refer to “Instru-
ment Cluster Display” in “Getting To Know Your Instru-
ment Panel” for further information.
An audible chime will be heard whenever a system error
has been detected.
See your authorized dealer for system service if normal
operation does not resume.
Operation
Pushing the Alternate Trailer Height (ATH) button once
while at Normal Ride Height (NRH), will lower the vehicle
to Alternate Trailer Height (ATH) and will illuminate the
LED.
NOTE: The LED will continuously blink until vehicle
Alternate Trailer Height (ATH) has been achieved and the
LED will turn off.
Pushing the Alternate Trailer Height (ATH) again will raise
the vehicle to Normal Ride Height (NRH).
NOTE: The LED will continuously blink until Normal Ride
Height (NRH) has been achieved.
• Transport Mode – No indicator lamps will be illumi-
nated. Transport Mode is disabled by driving the ve-
hicle.
• Tire/Jack Mode – No indicator lamps will be illumi-
nated. Tire/Jack Mode is disabled by driving the vehicle.
• Wheel Alignment Mode – No indicator lamps will be
illuminated. Wheel Alignment Mode is disabled by
driving the vehicle.
358 STARTING AND OPERATING
Recommended Distribution Hitch Adjustment
Towing With 1500 Air Suspension
1. Set air suspension to normal ride height. No action isrequired if already in normal ride height.
NOTE: The vehicle must remain in the engine run position
with all doors closed while attaching a trailer for proper
leveling of the air suspension system.
2. Position the truck to be ready to connect to the trailer (do not connect the trailer).
With Weight-Distributing Hitch (Correct)Improper Adjustment Of Weight-Distributing Hitch
(Incorrect)
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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 distribution 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. Preform a visual inspection of the trailer and weight
distributing hitch to confirm manufacturers’ recommen-
dations have been met.
Measurement Example Example 2500/3500
Height (mm)
H1 1030
H2 1058
H2-H1 28
(H2-H1)/2 14
(H2-H1)/2 + H1 1044
NOTE: For all towing conditions, we recommend towing
with tow haul mode engaged.
Towing With All Other 1500/2500/3500 (Non-Air Suspen-
sion)
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 distribution bars connected.
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frequent trailer towing.Refer to the “Maintenance Plan”
for the proper maintenance intervals.
NOTE: Check the automatic transmission fluid level be-
fore towing (6-speed automatic only).
Tow/Haul Mode
To reduce potential for automatic transmission overheat-
ing, activate TOW/HAUL mode when driving in hilly
areas, or select a lower gear range (using the Electronic
Range Select (ERS) shift control) on more severe grades.
Speed Control — If Equipped
• Do not use on hilly terrain or with heavy loads.
• When using the speed control, if you experience speed
drops greater than 10 mph (16 km/h), disengage until
you can get back to cruising speed.
• Use speed control in flat terrain and with light loads to
maximize fuel efficiency.
Cooling System
To reduce potential for engine and transmission overheat-
ing, take the following actions:
•City Driving
• In city traffic — while stopped, place the transmission in
NEUTRAL, but do not increase engine idle speed.
• Highway Driving
• Reduce speed.
• Air Conditioning
• Turn off temporarily.
Air Suspension System
To aid in attaching/detaching the trailer from the vehicle,
the air suspension system can be used. Refer to “Air
Suspension System” in “Starting And Operating” for fur-
ther information.
NOTE: The vehicle must remain in the engine running
position while attaching a trailer for proper leveling of the
air suspension system.
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RECREATIONAL TOWING (BEHIND MOTORHOME, ETC.)
Towing This Vehicle Behind Another Vehicle
Towing Condition Wheels OFFThe GroundTwo-Wheel
Drive Models Four-Wheel Drive Models
Flat Tow NONENOT
ALLOWED See Instructions
•
Automatic transmission in PARK
• Manual transmission in gear
(NOT in NEUTRAL)
• Transfer case in NEUTRAL (N)
• Tow in forward direction
Dolly Tow FrontNOT
ALLOWED NOT ALLOWED
Rear OK NOT ALLOWED
On Trailer ALLOK OK
NOTE:
• When towing your vehicle, always follow applicable
state and provincial laws. Contact state and provincial
Highway Safety offices for additional details.
• Vehicles equipped with air suspension must be placed in
Transport mode before tying them down (from the
body) on a trailer or flatbed truck. Refer to “Air Suspen-
sion – If Equipped” for more information. If the vehicle cannot be placed in Transport mode (for example, en-
gine will not run), tie-downs must be fastened to the
axles (not to the body). Failure to follow these instruc-
tions may cause fault codes to be set and/or cause loss
of proper tie-down tension.
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Recreational Towing — Two-Wheel Drive Models
DO NOT flat tow this vehicle. Damage to the drivetrain
will result.
Recreational towing (for two-wheel drive models) is al-
lowedONLY if the rear wheels are OFFthe ground. This
may be accomplished using a tow dolly or vehicle trailer. If
using a tow dolly, follow this procedure:
NOTE: If vehicle is equipped with air suspension, ensure
the vehicle is set to Normal Ride Height.
1. Properly secure the dolly to the tow vehicle, following the dolly manufacturer’s instructions.
2. Drive the rear wheels onto the tow dolly.
3. Firmly apply the parking brake. Place automatic trans- mission in PARK, manual transmission in gear (not in
NEUTRAL).
4. Properly secure the rear wheels to the dolly, following the dolly manufacturer’s instructions.
5. Turn the ignition OFF and remove the key fob.
6. Install a suitable clamping device, designed for towing, to secure the front wheels in the straight position.
CAUTION!
•Towing with the rear wheels on the ground will
cause severe transmission damage. Damage from
improper towing is not covered under the New
Vehicle Limited Warranty.
• Do not disconnect the driveshaft because fluid may
leak from the transmission, causing damage to inter-
nal parts.
Recreational Towing — Four-Wheel Drive Models
NOTE: Both the manual shift and electronic shift transfer
cases must be shifted into NEUTRAL (N) for recreational
towing. Automatic transmissions must be shifted into
PARK for recreational towing. Manual transmissions must
be placed in gear (NOT in NEUTRAL) for recreational
towing. Refer to the following for the proper transfer case
NEUTRAL (N) shifting procedure for your vehicle.
CAUTION!
• DO NOT dolly tow any 4WD vehicle. Towing with
only one set of wheels on the ground (front or rear)
will cause severe transmission and/or transfer case
(Continued)
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