Electronic Range Select (ERS) Operation —
Six-Speed Transmission (1500 Models Only)
The Electronic Range Select (ERS) shift control allows the
driver to limit the highest available gear when the trans-
mission is in DRIVE. For example, if you set the transmis-
sion gear limit to 4 (fourth gear), the transmission will not
shift above fourth gear, but will shift through the lower
gears normally.
Use of ERS (or TOW/HAUL mode) also enables an addi-
tional underdrive gear which is not normally used during
through-gear accelerations. This additional gear can im-
prove vehicle performance and cooling capability when
towing a trailer on certain grades. In ERS mode, gears 1
though 3 are underdrive gears, and ERS 4 is direct drive.
ERS 5 and 6 (Overdrive gears) are the same as the normal
fourth and fifth gears.
You can switch between DRIVE and ERS mode at any
vehicle speed. When the gear selector is in the DRIVE
position, the transmission will operate automatically, shift-
ing between all available gears. Tapping the ERS (-) switch
(column shift) or tapping the gear selector to the left (-)
(console shift) will activate ERS mode, display the current
gear in the instrument cluster, and set that gear as the top
available gear. For example, if you are in DRIVE and are inthird (direct) gear, when you tap the gear selector/switch
one time in the (-) direction, the display will show 4 (ERS
4 is direct gear). Another tap down (-) will shift the
transmission down to ERS 3 (the added underdrive gear).
Once in ERS mode, tapping (-) or (+) will change the top
available gear.
Column Gear Selector
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STARTING AND OPERATING 401
Overdrive Operation
The automatic transmission includes an electronically con-
trolled Overdrive (fourth and fifth gears). The transmission
will automatically shift into Overdrive if the following
conditions are present:
•The gear selector is in the DRIVE position,
• The transmission fluid has reached an adequate tem-
perature,
• The engine coolant (antifreeze) has reached an adequate
temperature,
• Vehicle speed is sufficiently high,
• The TOW/HAUL switch has not been activated, and
• 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 occurs,
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 transmission will automatically downshift (for engine braking) when the
throttle is closed and/or during steady braking maneu-
vers.
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.
TOW/HAUL Switch
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STARTING AND OPERATING 403
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.
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 downshifts,
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 driving 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 a heavy trailer), 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
408 STARTING AND OPERATING
gear range will improve performance and extend transmis-
sion life by reducing excessive shifting and heat buildup.
If the transmission temperature exceeds normal operating
limits, the powertrain controller will modify the transmis-
sion shift schedule and expand the range of torque con-
verter clutch engagement. This is done to prevent trans-
mission 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.
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 sig-
nificant additional heat load on the cooling system. Down-
shifting 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 tempera-
ture as well as vehicle speed. This feature improves warm
up time of the engine and transmission to achieve maxi-
mum 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 ex-
tremely cold temperatures (-16°F [-27°C] or below), opera-
tion may briefly be limited to first and direct gears only.
Normal operation will resume once the transmission tem-
perature has risen to a suitable level.
Transmission Limp Home Mode
Transmission function is monitored electronically for ab-
normal 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 damaging the trans-
mission.
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STARTING AND OPERATING 409
Overdrive Operation
The automatic transmission includes an electronically con-
trolled Overdrive (fifth and sixth gears). The transmission
will automatically shift into Overdrive if the following
conditions are present:
•The gear selector 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 occurs,
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 transmission will automatically downshift (for engine braking) when the
throttle is closed and/or during steady braking maneu-
vers.
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.
TOW/HAUL Switch
412 STARTING AND OPERATING
Wheel Alignment Mode
Before performing a wheel alignment, this mode must be
enabled. Refer to “Instrument Cluster Display” in “Under-
standing 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.
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.
NOTE: If towing with air suspension refer to “Trailer
Towing” in “Starting And Operating” for further informa-
tion.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 “Understanding Your Instrument
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.
442 STARTING AND OPERATING
Tire/Jack Mode
To assist with changing a tire, the air suspension system
has a feature which allows the automatic leveling to be
disabled. Refer to “Instrument Cluster Display” in “Under-
standing 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.
Transport Mode
For towing your vehicle with four wheels off the road, the
air suspension system has a feature which will put the
vehicle into Entry/Exit height and disable the automatic
load leveling system. Refer to “Instrument Cluster Dis-
play” in “Understanding 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 “Under-
standing 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.
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.
NOTE: If towing with air suspension refer to “Trailer
Towing” in “Starting And Operating” for further informa-
tion.
448 STARTING AND OPERATING
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 min-
utes 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. 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.
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STARTING AND OPERATING 451