If the light remains lit with the engine running, your
vehicle will usually be drivable. However, see an autho-
rized dealer for service as soon as possible. If the light is
flashing when the engine is running, immediate service is
required. You may experience reduced performance, an
elevated/rough idle or engine stall and your vehicle may
require towing.
28. Air Suspension Normal Ride Height Indicator Lamp
– If Equipped
This light will illuminate when the air suspension system
is set to the Normal Ride Height setting. For further
information, refer to “Air Suspension System” in “Start-
ing And Operating”.
29. Air Suspension Off-Road 1 Indicator Lamp – If
Equipped
This light will illuminate when the air suspension system is
set to the Off-Road 1 setting. For further information, refer to
“Air Suspension System” in “Starting And Operating”.
30. Air Suspension Off-Road 2 Indicator Lamp – If
Equipped
This light will illuminate when the air suspension system
is set to the Off-Road 2 setting. For further information,
refer to “Air Suspension System” in “Starting And
Operating”.
31. 4 LOWThis light alerts the driver that the vehicle is in
the four-wheel drive LOW mode. The front and
rear driveshafts are mechanically locked to-
gether forcing the front and rear wheels to
rotate at the same speed. Low range provides a greater
gear reduction ratio to provide increased torque at the
wheels.
For further information on four-wheel drive operation
and proper use, refer to “Four-Wheel Drive Operation —
If Equipped” in “Starting And Operating”.
4
UNDERSTANDING YOUR INSTRUMENT PANEL 295
range will improve performance and extend transmission
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.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
418 STARTING AND OPERATING
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.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
424 STARTING AND OPERATING
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). To drive, move the shift
lever from PARK or NEUTRAL to the DRIVE position.
Pull the shift lever toward you when shifting into RE-
VERSE 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 newvehicle may be somewhat abrupt. This is a normal
condition, and precision shifts will develop within a few
hundred miles (kilometers).
Only shift from DRIVE to PARK or REVERSE when the
accelerator pedal is released and the vehicle is stopped.
Be sure to keep your foot on the brake pedal when
shifting between these gears.
The transmission shift lever has only PARK, REVERSE,
NEUTRAL, and DRIVE shift positions. Manual down-
shifts can be made using the Electronic Range Select
(ERS) shift control (refer to “Electronic Range Select (ERS)
Operation” in this section). Pressing the ERS (-/+)
switches (on the shift lever) while in the DRIVE position
will select the highest available transmission gear, and
will display that gear in the instrument cluster as 1, 2, 3,
etc.
5
STARTING AND OPERATING 425
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 condi-
tions, 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) to select a lower
gear range. Under these conditions, using a lower gear
range will improve performance and extend transmission
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.
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.
430 STARTING AND OPERATING
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 isselected. 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.
2. Shift the transmission into PARK.
3. Turn the ignition switch to the OFF position.
4. Wait approximately 10 seconds.
5. Restart the engine.
6. Shift into the desired gear range. If the problem is no
longer detected, the transmission will return to normal
operation.
5
STARTING AND OPERATING 431
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.NOTE:
•
The torque converter clutch will not engage, and the
transmission will not shift to sixth gear, until the
transmission fluid and engine coolant are warm [usu-
ally after 1 to 3 miles (2 to 5 km) of driving]. Because
sixth gear is disabled, and engine speed is higher when
the torque converter clutch is not engaged, it may
seem as if the transmission is not shifting properly
when cold. This is normal. Using the Electronic Range
Select (ERS) shift control, when the transmission is
sufficiently warm, will demonstrate that the transmis-
sion 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
5
STARTING AND OPERATING 435
cause damage to the transmission. The torque con-
verter will refill within five seconds after starting the
engine.
FOUR-WHEEL DRIVE OPERATION — IF
EQUIPPED
Four-wheel drive trucks are equipped with either a
manually shifted transfer case or an electronically shifted
transfer case. Refer to the operating instructions for your
transfer case, located in this section for further informa-
tion.
Manually Shifted Transfer Case — If Equipped
The transfer case provides four mode positions.
•Two-wheel drive high range (2H)
• Four-wheel drive high range (4H)
• Neutral (N)
• Four-wheel drive low range (4L) 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
positions can be used to lock the front and rear drive-
shafts together and force the front and rear wheels to
rotate at the same speed. This is accomplished by simply
moving the shift lever 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 dam-
age to the driveline components.
The “Transfer Case Position Indicator Light” in the
instrument cluster will alert the driver that the vehicle is
in four-wheel drive and that the front and rear drive-
shafts are locked together. This light will illuminate when
436 STARTING AND OPERATING