Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:The vehicle does not need an elaborate
break-in. But it will perform better in the long run if
you follow these guidelines:
.Keep your speed at 55 mph (88 km/h) or less
for the first 500 miles (805 km).
.Do not drive at any one constant speed, fast
or slow, for the first 500 miles (805 km).
Do not make full-throttle starts. Avoid
downshifting to brake or slow the vehicle.
.Avoid making hard stops for the first
200 miles (322 km) or so. During this time the
new brake linings are not yet broken in. Hard
stops with new linings can mean premature
wear and earlier replacement. Follow this
breaking-in guideline every time you get new
brake linings.
.Do not tow a trailer during break-in.
See Towing a Trailer
on page 6‑42for the
trailer towing capabilities of the vehicle and
more information.
Following break‐in, engine speed and load can be
gradually increased.
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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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WARNING: (Continued)
even death. Never run the engine in an enclosed
area that has no fresh air ventilation. For more
information, seeEngine Exhaust on page 3‑44.
{WARNING:
It can be dangerous to get out of the vehicle if the
automatic transmission 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).
Follow the proper steps to be sure the vehicle will not
move. See Shifting Into Park on page 3‑41.
If parking on a hill and pulling a trailer, see Towing a
Trailer on page 6‑42.
Mirrors
Manual Rearview Mirror
Hold the inside rearview mirror in the center to move it
for a clearer view behind your vehicle. Adjust the mirror
to avoid glare from the headlamps behind you. Push the
tab forward for daytime use and pull it for nighttime use.
Automatic Dimming Rearview Mirror
This vehicle may have an automatic dimming inside
rearview mirror with OnStar®. It may also have
Intellibeam®. For more information on Intellibeam™, see
“Intellibeam™ Intelligent High‐Beam Headlamp Control
System” underExterior Lamps
on page 4‑10. For more
information on OnStar®, see the OnStar®owner's guide.
Automatic Dimming Mirror Operation
Automatic dimming reduces the glare of lights from
behind the vehicle. The dimming feature comes on and
the indicator light illuminates each time the vehicle is
started.
O(On/Off): Press to turn the dimming feature on or off.
Cleaning the Mirror
Do not spray glass cleaner directly on the mirror. Use a
soft towel dampened with water.
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