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WARNING: (Continued)
You could be seriously injured. Plug the cord into
a properly grounded three-prong 110-volt AC
outlet. If the cord will not reach, use a heavy-duty
three-prong extension cord rated for at least
15 amps.
4. Before starting the engine, be sure to unplug and store the cord as it was before to keep it away from
moving engine parts. If you do not, it could be
damaged.
The length of time the heater should remain plugged in
depends on several factors. Ask a dealer/retailer in the
area where you will be parking the vehicle for the best
advice on this.
Active Fuel Management™
Vehicles with V8 engines may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders, depending
on the driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate in the
half cylinder mode, allowing the vehicle to achieve
better fuel economy. When greater power demands are required, such as accelerating from a stop, passing,
or merging onto a freeway, the system will maintain
full-cylinder operation.
If the vehicle has an Active Fuel Management™
indicator, see
DIC Operation and Displays
on
page 4‑40for more information on using this display .
Automatic Transmission Operation
The vehicle has a Hydra-Matic®6L80 automatic
transmission, and has an electronic shift position
indicator within the instrument panel cluster. The
electronic shift position indicator displays when the
shift lever is moved out of P (Park).
There are several different positions for the shift lever.
P (Park) : This position locks the rear wheels. It is the
best position to use when you start the engine because
the vehicle cannot move easily.
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When parked on a hill, especially when the vehicle has
a heavy load, you may notice an increase in the effort
to shift out of P (Park). See Torque Lock (Automatic
Transmission) underShifting Into Park
on page 3‑41for more information.
{WARNING:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
firmly set. The vehicle can roll.
Do not leave the vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure the
vehicle will not move, even when you are on fairly
level ground, always set the parking brake and
move the shift lever to P (Park). See Shifting Into
Park
on page 3‑41. If you are pulling a trailer,
see Towing a Trailer on page 6‑42.
R (Reverse) : Use this gear to back up.
Notice: Shifting to R (Reverse) while the vehicle is
moving forward could damage the transmission.
The repairs would not be covered by the vehicle
warranty. Shift to R (Reverse) only after the vehicle
is stopped. To rock the vehicle back and forth to get out of snow,
ice, or sand without damaging the transmission, see
If
Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on
page 6‑30.
N (Neutral) : In this position, the engine does not
connect with the wheels. To restart when you are
already moving, use N (Neutral) only. Also, use
N (Neutral) when the vehicle is being towed.
{WARNING:
Shifting into a drive gear while the engine is
running at high speed is dangerous. Unless your
foot is firmly on the brake pedal, the vehicle could
move very rapidly. You could lose control and hit
people or objects. Do not shift into a drive gear
while the engine is running at high speed.
Notice: Shifting out of P (Park) or N (Neutral) with
the engine running at high speed may damage the
transmission. The repairs would not be covered
by the vehicle warranty. Be sure the engine is not
running at high speed when shifting the vehicle.
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D (Drive) :This position is for normal driving. It provides
the best fuel economy. If you need more power for
passing, and you are:
.Going less than about 35 mph (55 km/h), push the
accelerator pedal about halfway down.
.Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
By doing this, the vehicle shifts down to the next gear
and has more power.
D (Drive) can be used when towing a trailer, carrying a
heavy load, driving on steep hills, or for off-road driving.
You may want to shift the transmission to a lower gear
selection if the transmission shifts too often.
Downshifting the transmission in slippery road
conditions could result in skidding, see Skidding under
Loss of Control on page 6‑12.
M (Manual Mode) : This position lets drivers select
the range of gears appropriate for current driving
conditions. See Driver Shift Control (DSC) later in this
section.
Notice: Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator pedal
may damage the transmission. The repair will not be
covered by the vehicle warranty. If you are stuck, do
not spin the tires. When stopping on a hill, use the
brakes to hold the vehicle in place. The vehicle has a shift stabilization feature that
adjusts the transmission shifting to the current driving
conditions in order to reduce rapid upshifts and
downshifts. This shift stabilization feature is designed to
determine, before making an upshift, if the engine will
be able to maintain vehicle speed by analyzing things
such as vehicle speed, throttle position and vehicle
load. If the shift stabilization feature determines that a
current vehicle speed cannot be maintained, the
transmission does not upshift and instead holds the
current gear. In some cases, this may appear to be a
delayed shift, however the transmission is operating
normally.
The vehicle's transmission uses adaptive shift controls
that compares key shift parameters to pre-programmed
ideal shifts stored in the transmissions computer. The
transmission constantly makes adjustments to improve
vehicle performance according to how the vehicle is
being used, such as with a heavy load or when
temperature changes. During this adaptive shift controls
process, shifting may feel different as the transmission
determines the best settings.
When temperatures are very cold, the Hydra-Matic
®
6L80 automatic transmission's gear shifting may be
delayed providing more stable shifts until the engine
warms up. Shifts may be more noticeable with a cold
transmission. This difference in shifting is normal.
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Driver Shift Control (DSC)
The vehicle has Driver Shift Control (DSC). DSC
controls the vehicle's transmission and vehicle speed
while driving down hill or towing a trailer by allowing you
to select a desired range of gears.
To use this feature, do the following:1. Move the shift lever to the M (Manual Mode).
2. Press the plus/minus button, to upshift or downshift selecting the desired range of gears for current
driving conditions. The DIC display will show the message MANUAL
SHIFT on the first line and the current gear will be
displayed on the second line. See
Driver Information
Center (DIC)
on page 4‑39and DIC Operation and
Displayson page 4‑40for more information. The
number displayed in the DIC is the highest gear that
can be used. However, the vehicle can automatically
shift to lower gears as it adjusts to driving conditions.
This means that all gears below that number are
available. When 5 (Fifth) is selected, 1 (First) through
5 (Fifth) gears are automatically shifted by the vehicle,
but 6 (Sixth) cannot be used until the plus/minus button
located on the steering column lever is used to change
to the gear.
Grade Braking is not available when the Driver Shift
Control is active. See Tow/Haul Mode
on page 3‑39for
more information.
While using the DSC, cruise control and the tow/haul
mode can be used.
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Tow/Haul Mode
The vehicle has a tow/haul mode. The tow/haul mode
adjusts the transmission shift pattern to reduce shift
cycling, providing increased performance, vehicle
control, and transmission cooling when towing or
hauling heavy loads.
Press the button located on the end of the shift lever to
turn the tow/haul on or off. When the tow/haul is on, a
light on the instrument panel cluster will come on.
SeeTow/Haul Mode Light
on page 4‑39for more
information. Also see
“Tow Haul Mode” underTowing a Trailer
on
page 6‑42for more information.
The tow/haul mode works with the Autoride
®feature,
if the vehicle has this, to enhance the ride when
trailering or with a loaded vehicle. See Autoride
®on
page 6‑41.
Grade Braking
The Grade Braking shift modes can be activated by
pressing the button on the end of the shift control lever.
While in Range Selection Mode, Grade Braking is
deactivated allowing the driver to select a desired range
of gears.
Grade Braking is only active while the Tow/Haul Mode
is selected and you are not in the Range Selection
Mode. See “Tow/Haul Mode listed previously and
Automatic Transmission Operation
on page 3‑35for
more information on the Range Selection Mode.
Grade Braking assists in maintaining desired
vehicle speeds when driving on downhill grades by
automatically implementing a shift schedule that utilizes
the engine and transmission to slow the vehicle.
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This reduces wear on the braking system and increases
control of the vehicle. Grade Braking monitors vehicle
speed, acceleration, engine torque and brake pedal
usage. Using this information, it detects when the
vehicle is on a downhill grade and the driver desires
to slow the vehicle by pressing the brake.
Also seeTowing a Trailer
on page 6‑42for more
information.
Cruise Grade Braking
Cruise Grade Braking assists when driving on a
downhill grade. It maintains vehicle speed by
automatically implementing a shift schedule that uses
the engine and the transmission to slow the vehicle.
Cruise Grade Braking operates while Cruise Control is
engaged in Tow/Haul mode to assist in maintaining
vehicle speed under loaded vehicle conditions.
It utilizes vehicle acceleration and deviation from
desired speed to determine the correct gear for the
operating condition. If vehicle speed is above the
desired speed the transmission will downshift to slow
the vehicle. If vehicle speed is near or below desired
speed the trans will upshift, allowing vehicle speed to
increase.
While in the Range Select Mode (RSM) mode, cruise
grade braking is not available.
See Automatic Transmission Operation on page 3‑35.
Parking Brake
Set the parking brake by holding the regular brake
pedal down, then pushing down the parking brake
pedal.
If the ignition is on, the brake system warning light
will come on. See Brake System Warning Light
on
page 4‑31.
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Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the
brake warning light is off before driving.
To release the parking brake, hold the regular brake
pedal down, then push down momentarily on the
parking brake pedal until you feel the pedal release.
Slowly pull your foot up off the park brake pedal. If the
parking brake is not released when you begin to drive,
the brake system warning light will flash and a chime
will sound warning you that the parking brake is still on.
If you are towing a trailer and are parking on a hill, see
Towing a Trailer on page 6‑42.Shifting Into Park
{WARNING:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake firmly set. The vehicle can roll. If you have
left the engine running, the vehicle can move
suddenly. You or others could be injured. To be
sure the vehicle will not move, even when you are
on fairly level ground, use the steps that follow.
If you are pulling a trailer, see Towing a Trailer
on
page 6‑42
.
1. Hold the brake pedal down, then set the parking brake.
2. Move the shift lever into the P (Park) position by pulling the shift lever toward you and moving it up
as far as it will go.
3. Turn the ignition key to LOCK/OFF.
4. Remove the key and take it with you. If you can leave the vehicle with the ignition key in your hand,
the vehicle is in P (Park).
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Leaving the Vehicle With the Engine
Running
{WARNING:
It can be dangerous to leave the vehicle with the
engine running. The vehicle could move suddenly
if the shift lever is not fully in P (Park) with the
parking brake firmly set. And, if you leave the
vehicle with the engine running, it could overheat
and even catch fire. You or others could be
injured. Do not leave the vehicle with the engine
running.
If you have to leave the vehicle with the engine running,
be sure the vehicle is in P (Park) and the parking brake
is firmly set. After the shift lever is moved into P (Park),
hold the regular brake pedal down. Then, see if you can
move the shift lever away from P (Park) without first
pulling it toward you. If you can, it means that the shift
lever was not fully locked into P (Park).
Torque Lock
If you are parking on a hill and you do not shift the
transmission into P (Park) properly, the weight of the
vehicle can put too much force on the parking pawl
in the transmission. It might be difficult to pull the
shift lever out of P (Park). This is called torque lock.
To prevent torque lock, set the parking brake and then
shift into P (Park) properly before you leave the driver
seat. To find out how, see Shifting Into Park
on
page 3‑41.
When you are ready to drive, move the shift lever out of
P (Park) before releasing the parking brake.
If torque lock does occur, you might need to have
another vehicle push yours a little uphill to take some of
the pressure from the parking pawl in the transmission.
Then you should be able to pull the shift lever out of
P (Park).
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