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 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.
5
STARTING AND OPERATING 305
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 the torque
converter clutch is inhibited until the transmission fluid
is warm (refer to the “Note” under “Torque Converter
Clutch” in this section). On models with 66RFE transmis-
sion, top overdrive gear is also inhibited until the trans-
mission fluid is warm, and during extremely cold tem-
peratures (-16°F [-27°C] or below), operation may briefly
be limited to first and direct gears only. On trucks with
AS66RC transmission, fifth and sixth gears may be
inhibited briefly on cold starts below 41°F (5°C), and
during very cold temperatures (-4°F [-20°C] or below),
operation may briefly be limited to third gear only.
During this condition, the ability of the vehicle to accel-
erate under heavily loaded conditions may be reduced.
306 STARTING AND OPERATING
WARNING!
Do not downshift for additional engine braking on a
slippery surface. The drive wheels could lose their
grip and the vehicle could skid, causing a collision or
personal injury.
NOTE: To select the proper gear position for maximum
deceleration (engine braking), simply press and hold the
ERS (-) switch down. The transmission will shift to the
range from which the vehicle can best be slowed down.
CAUTION!
When using ERS for engine braking while descend-
ing steep grades, be careful not to overspeed the
engine. Apply the brakes as needed to prevent en-
gine overspeed.
Overdrive Operation
The automatic transmission includes an electronically
controlled Overdrive (fifth and sixth gears). The trans-
mission will automatically shift into Overdrive if the
following conditions are present:
• The shift lever 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.
When To Use TOW/HAUL Mode
When driving in hilly areas, towing a trailer, carrying a
heavy load, etc., and frequent transmission shifting occurs,
press the TOW/HAUL switch to activate TOW/HAUL
5
STARTING AND OPERATING 309
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) during
steady braking maneuvers.The “TOW/HAUL Indicator Light” will illuminate in the
instrument cluster to indicate that TOW/HAUL mode
has been activated. Pressing 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 pressed each time the engine
is started.
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.
TOW/HAUL Switch
310 STARTING AND OPERATING
Proper operation of four-wheel drive vehicles depends
on tires of equal size, type and circumference on each
wheel. Any difference will adversely affect shifting and
can cause damage to the drivetrain.
NOTE:Do not attempt to make a shift while only the
front or rear wheels are spinning. The front and rear
driveshaft speeds must be equal for the shift to take
place. Shifting while only the front or rear wheels are
spinning can cause damage to the transfer case.
Because four-wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
NOTE: Delayed shifts out of four-wheel drive may be
experienced due to uneven tire wear, low or uneven tire
pressures, excessive vehicle loading, or cold tempera-
tures.WARNING!
You or others could be injured or killed if you leave
the vehicle unattended with the transfer case in the
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
disengages both the front and rear drive shafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
For additional information on the appropriate use of each
transfer case mode position, see the information below:
2H
Rear-Wheel Drive High Range — This range is for
normal street and highway driving on dry hard surfaced
roads.
5
STARTING AND OPERATING 313
the control knob back to the current position, wait five
seconds, and retry selection. To find the shift require-
ments, refer to theShifting 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 function-
ing properly and that service is required.
WARNING!
Always engage the parking brake when powering
down the vehicle if the “SVC 4WD Warning Light” is
illuminated. Not engaging the parking brake may
allow the vehicle to roll, which may cause personal
injury. NOTE:
Do not attempt to make a shift while only the
front or rear wheels are spinning, as this can cause
damage to driveline components.
When operating your vehicle in 4WD LOW, the engine
speed is approximately three times that of the 2WD or
4WD LOCK positions at a given road speed. Take care
not to overspeed the engine and do not exceed 25 mph
(40 km/h).
Proper operation of four-wheel drive vehicles depends
on tires of equal size, type and circumference on each
wheel. Any difference in tire size can cause damage to the
drivetrain.
Because four-wheel drive provides improved traction,
there is a tendency to exceed safe turning and stopping
speeds. Do not go faster than road conditions permit.
318 STARTING AND OPERATING
WARNING!
You or others could be injured or killed if you leave
the vehicle unattended with the transfer case in the
NEUTRAL position without first fully engaging the
parking brake. The transfer case NEUTRAL position
disengages both the front and rear drive shafts from
the powertrain and will allow the vehicle to move
regardless of the transmission position. The parking
brake should always be applied when the driver is
not in the vehicle.
For additional information on the appropriate use of each
transfer case mode position, see the information below:
2WD
Rear Wheel Drive High Range — This range is for normal
street and highway driving on dry, hard surfaced roads. 4WD LOCK
Four-Wheel Drive Lock Range — This range maximizes
torque to the front driveshaft, forcing the front and rear
wheels to rotate at the same speed. This range provides
additional traction for loose, slippery road surfaces only.
4WD LOW
Four-Wheel Drive Low Range — This range provides low
speed four-wheel drive. It maximizes torque to the front
driveshaft, forcing the 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).
NEUTRAL (N)
Neutral — This range disengages both the front and rear
driveshafts from the powertrain. To be used for flat
5
STARTING AND OPERATING 319
NOTE:
•If Steps 1 or 2 of either the Preferred or Alternate
Procedure are not satisfied prior to attempting the
shift, then the desired position indicator light will flash
continuously while the original position indicator light
is ON, until all requirements have been met.
• The ignition switch must be in the ON position for a
shift to take place and for the position indicator lights
to be operable. If the ignition switch is not in the ON
position, the shift will not take place and no position
indicator lights will be on or flashing.
LIMITED-SLIP DIFFERENTIAL
The limited-slip differential provides additional traction
on snow, ice, mud, sand and gravel, particularly when
there is a difference between the traction characteristics
of the surface under the right and left rear wheels. During normal driving and cornering, the limited-slip unit per-
forms similarly to a conventional differential. On slip-
pery surfaces, however, the differential delivers more of
the driving effort to the rear wheel having the better
traction.
The limited-slip differential is especially helpful during
slippery driving conditions. With both rear wheels on a
slippery surface, a slight application of the accelerator
will supply maximum traction. When starting with only
one rear wheel on an excessively slippery surface, slight
momentary application of the parking brake may be
necessary to gain maximum traction.WARNING!
On vehicles equipped with a limited-slip differential
never run the engine with one rear wheel off the
ground since the vehicle may drive through the rear
(Continued)
322 STARTING AND OPERATING