2006 GMC YUKON XL trailer

Starting and Operating
Your Vehicle
New Vehicle Break-In
Notice:Your 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 rst 500 miles (805 km).
Do not drive at any one constant speed, fast or
slow, for the rst 500 miles (805 km). Do not
make full-throttle starts. Avoid downshifting to
brake, or slow, the vehicle.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time your 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. SeeTowing
a Trailer on page 4-60for the trailer towing
capabilities of your vehicle and more
information.
Following break-in, engine speed and load can be
gradually increased.
Ignition Positions
Use the key to turn the ignition switch to four different
positions.
A (LOCK):This position locks the ignition and
transmission. It is a theft-deterrent feature. You will only
be able to remove the key when the ignition is turned
to LOCK.
Notice:Using a tool to force the key from the
ignition switch could cause damage or break the
key. Use the correct key and turn the key only with
your hand. Make sure the key is all the way in.
If it is, turn the steering wheel left and right while
you turn the key hard. If none of this works,
then your vehicle needs service.
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Automatic Transmission Operation
There are several different positions for your shift lever.
Your vehicle is equipped with an automatic transmission
and features an electronic shift position indicator
within the instrument panel cluster. This display must
be powered anytime the shift lever is capable of
being moved out of PARK (P).
PARK (P):This position locks your rear wheels.
It is the best position to use when you start your
engine because your vehicle cannot move easily.
{CAUTION:
It is dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake rmly set. Your vehicle can roll.
Do not leave your 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.
CAUTION: (Continued)
CAUTION: (Continued)
To be sure your vehicle will not move, even
when you are on fairly level ground, always
set your parking brake and move the shift
lever to PARK (P). SeeShifting Into Park (P)
on page 2-32. If you are pulling a trailer, see
Towing a Trailer on page 4-60.
{CAUTION:
If you have four-wheel drive, your vehicle
will be free to roll — even if your shift lever
is in PARK (P) — if your transfer case is in
NEUTRAL. So, be sure the transfer case is
in a drive gear, two-wheel high, four-wheel
high or four-wheel low — not in NEUTRAL.
SeeShifting Into Park (P) on page 2-32.
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REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage the transmission.
The repairs would not be covered by your warranty.
Shift to REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of
snow, ice or sand without damaging your transmission,
seeIf Your Vehicle is Stuck in Sand, Mud, Ice or
Snow on page 4-44.
NEUTRAL (N):In this position, your engine does not
connect with the wheels. To restart when you are
already moving, use NEUTRAL (N) only. Also, use
NEUTRAL (N) when your two-wheel drive vehicle
is being towed.
{CAUTION:
Shifting into a drive gear while your engine is
running at high speed is dangerous. Unless
your foot is rmly on the brake pedal, your
vehicle could move very rapidly. You could
lose control and hit people or objects. Do not
shift into a drive gear while your engine is
running at high speed.Notice:Shifting out of PARK (P) or NEUTRAL (N)
with the engine running at high speed may damage
the transmission. The repairs would not be covered
by your warranty. Be sure the engine is not running
at high speed when shifting your vehicle.
DRIVE (D):This position is for normal driving.
If you need more power for passing, and you are:
Going less than about 35 mph (56 km/h), push
your accelerator pedal about halfway down.
Going about 35 mph (56 km/h) or more, push
the accelerator all the way down.
You will shift down to the next gear and have
more power.
DRIVE (D) 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
THIRD (3) or, if necessary, a lower gear selection if
the transmission shifts too often.
THIRD (3):This position is also used for normal driving,
however it offers more power and lower fuel economy
than DRIVE (D).
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SECOND (2):This position gives you more power
but lower fuel economy. You can use SECOND (2) on
hills. It can help control your speed as you go down
steep mountain roads, but then you would also want
to use your brakes off and on.
If you manually select SECOND (2) in a light duty
automatic transmission, the transmission will drive in
second gear. You may use this feature for reducing the
speed of the rear wheels when you are trying to start
your vehicle from a stop on slippery road surfaces.
FIRST (1):This position gives you even more
power (but lower fuel economy) than SECOND (2).
You can use it on very steep hills, or in deep snow or
mud. If the shift lever is put in FIRST (1) while the
vehicle is moving forward, the transmission will not shift
into rst gear until the vehicle is going slowly enough.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator pedal
may damage the transmission. If you are stuck,
do not spin the tires. When stopping on a hill, use
the brakes to hold the vehicle in place.
On cold days, approximately 32°F (0°C) or colder,
your transmission is designed to shift differently until
the engine reaches normal operating temperature.
This is intended to improve heater performance.Tow/Haul Mode
Your vehicle may be equipped with a Tow/Haul mode.
If so, the selector button is located on the end of the
column shift lever. You can use this feature to assist
when towing or hauling a heavy load. SeeTowing a
Trailer on page 4-60for more information.
2-25

When Tow/Haul mode
is selected the
Tow/Haul indicator
light will illuminate.
The Tow/Haul mode also interacts with the Autoride
®
feature, if equipped, to enhance the ride when trailering
or with a loaded vehicle. SeeAutoride®on page 4-60.
Four-Wheel Drive
If your vehicle has four-wheel drive, you will see the
buttons shown below. You can send your engine’s
driving power to all four wheels for extra traction.
To get the most satisfaction out of four-wheel drive,
you must be familiar with its operation. Read the
part that follows before using four-wheel drive.
Notice:Driving on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive Low for
an extended period of time may cause premature
wear on your vehicle’s powertrain. Do not drive on
clean, dry pavement in Four-Wheel Drive High or
Four-Wheel-Drive Low for extended periods of time.The transfer case buttons
are located to the left
of the instrument panel
cluster.
The front axle locks and unlocks automatically when
you shift the transfer case. Some delay for the axle
to lock or unlock is normal.
For information on StabiliTrak
®, seeStabiliTrak®
System on page 4-9.
Use these buttons to shift into and out of
four-wheel drive.
2-26

Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and the warning light will ash
when the parking brake is applied and the vehicle
is moving at least 3 mph (5 km/h) for at least
three seconds.
To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol, to release the parking brake.If the ignition is on when the parking brake is released,
the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Verify that
the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-60.
2-31

Shifting Into Park (P)
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake rmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle
will not move, even when you are on fairly
level ground, use the steps that follow.
With four-wheel drive, if your transfer case
is in NEUTRAL, your vehicle will be free to
roll, even if your shift lever is in PARK (P).
So, be sure the transfer case is in a drive
gear — not in NEUTRAL. If you are pulling
a trailer, seeTowing a Trailer on page 4-60.1. Hold the brake pedal down with your right foot
and set the parking brake.
2. Move the shift lever into the PARK (P) position
by pulling the shift lever toward you and moving
it up as far as it will go.
3. Be sure the transfer case is in a drive
gear — not in NEUTRAL (N).
4. Turn the ignition key to LOCK.
5. Remove the key and take it with you. If you
can leave your vehicle with the ignition key in
your hand, your vehicle is in PARK (P).
2-32

{CAUTION:
Four-wheel drive vehicles with the transfer
case in NEUTRAL will allow the vehicle to roll,
even if your shift lever is in PARK (P). So, be
sure the transfer case is in a drive gear — not
in NEUTRAL. Always set your parking brake.
Follow the proper steps to be sure your vehicle will
not move. SeeShifting Into Park (P) on page 2-32.
If you are pulling a trailer, seeTowing a Trailer
on page 4-60.
Mirrors
Manual Rearview Mirror
Pull the tab under the mirror toward you to reduce glare
from headlamps behind you after dark. Push the tab
away from you for normal daytime operation.
Automatic Dimming Rearview Mirror
with OnStar
®and Compass
Your vehicle may have an automatic-dimming rearview
mirror with a compass and the OnStar®system.
There are three additional buttons for the OnStar
®
system. See your dealer for more information on
the system and how to subscribe to OnStar®.
SeeOnStar®System on page 2-50for more
information about the services OnStar®provides.
2-37