2009 GMC YUKON towing

Tow/Haul Mode
The vehicle has a Tow/Haul mode. 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 or if there is a need to charge a battery
installed in a trailer. SeeTowing a Trailer on page 4-52
for more information.When Tow/Haul mode is
selected the Tow/Haul
indicator light will come on.
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. SeeAutoride
®on
page 4-51.
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Grade Braking (Hydra-Matic®6-Speed
Automatic Transmission)
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 andAutomatic
Transmission Operation on page 2-29for 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. 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 truck is on a downhill grade and the
driver desires to slow the vehicle by pressing the brake.
Also seeTowing a Trailer on page 4-52for more
information.
Cruise Grade Braking (Hydra-Matic®
6-Speed Automatic Transmission)
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.
SeeAutomatic Transmission Operation on page 2-29.
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2m(Two-Wheel Drive High):This setting is used for
driving in most street and highway situations. The
front axle is not engaged in two-wheel drive. This setting
also provides the best fuel economy.
AUTO (Automatic Four-Wheel Drive):This setting is
ideal for use when road surface traction conditions are
variable. When driving your vehicle in AUTO, the front
axle is engaged, but the vehicle’s power is primarily sent
to the rear wheels. When the vehicle’s software
determines a need for more traction, the system will
transfer more power to the front wheels. Driving in this
mode results in slightly lower fuel economy than
Two-Wheel Drive High.
4
m(Four-Wheel Drive High):Use the four-wheel high
position when you need extra traction, such as on snowy
or icy roads or in most off-road situations. This setting
also engages your front axle to help drive the vehicle.
This is the best setting to use when plowing snow.
4
n(Four-Wheel Drive Low):This setting also engages
the front axle and delivers extra torque. You may never
need this setting. It sends maximum power to all four
wheels. You might choose Four-Wheel Drive Low if you
are driving off-road in deep sand, deep mud, deep snow,
and while climbing or descending steep hills.
The vehicle has StabiliTrak
®. Shifting into
Four-Wheel-Drive Low will turn Traction Control and
StabiliTrak
®off. SeeStabiliTrak®System on page 4-6.
{CAUTION:
Shifting the transfer case to N (Neutral) can cause
the vehicle to roll even if the transmission is in
P (Park). You or someone else could be seriously
injured. Be sure to set the parking brake before
placing the transfer case in N (Neutral). See
Parking Brake on page 2-42.
N (Neutral):Shift the vehicle’s transfer case to
N (Neutral) only when towing the vehicle. See
Recreational Vehicle Towing on page 4-44orTowing
Your Vehicle on page 4-44for more information.
If the SERVICE 4 WHEEL DRIVE message stays on,
you should take the vehicle to your dealer/retailer
for service. See “SERVICE 4 WHEEL DRIVE message”
underDIC Warnings and Messages on page 3-64.
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Parking Brake
For vehicles with a release handle, 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. SeeBrake System Warning Light on
page 3-40.A chime sounds and the warning light ashes when the
parking brake is applied and the vehicle is moving at
least 5 mph (8 km/h).
To release the parking brake, hold the regular brake
pedal down. Then pull the bottom edge of the lever with
the parking brake symbol, located above the parking
brake pedal.
If the ignition is on when the parking brake is released,
the brake system warning light goes off.
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.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-52.
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For vehicles without a release handle, 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. SeeBrake System Warning Light on
page 3-40.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 ash 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 4-52.
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Shifting Into Park
{CAUTION:
It can be dangerous to get out of the vehicle if the
shift lever is not fully in P (Park) with the parking
brake rmly 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. With
four-wheel drive, if the transfer case is in Neutral,
the vehicle will be free to roll, even if the shift lever
is in P (Park). 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 4-52.
1. Hold the brake pedal down, then set the parking
brake.
SeeParking Brake on page 2-42for more
information.
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. Be sure the transfer case is in a drive gear — not
in N (Neutral).
4. Turn the ignition key to LOCK/OFF.
5. 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).
Leaving the Vehicle With the Engine
Running
{CAUTION:
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 rmly set.
If you have four-wheel drive and the transfer case
is in Neutral, the vehicle will be free to roll, even if
the shift lever is in P (Park). So be sure the
transfer case is in a drive gear — not in Neutral.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re. You
or others could be injured. Do not leave the vehicle
with the engine running unless you have to.
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{CAUTION:
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 rmly 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).
{CAUTION:
Four-wheel drive vehicles with the transfer case
in N (Neutral) will allow the vehicle to roll, even
if the automatic transmission shift lever is in
P (Park). So, be sure the transfer case is in a
drive gear — not in N (Neutral). Always set the
parking brake.Follow the proper steps to be sure the vehicle will not
move. SeeShifting Into Park on page 2-44.
If pulling a trailer, seeTowing a Trailer on page 4-52.
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
The vehicle may have an automatic dimming rearview
mirror.
Vehicles with OnStar
®have three additional control
buttons for the OnStar®system. See your dealer/retailer
for more information about OnStar®and how to
subscribe to it. SeeOnStar®System on page 2-64for
more information about the services OnStar®provides.
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O(On/Off):Press to turn the dimming feature on
or off.
The vehicle may also have a Rear Vision Camera
(RVC). SeeRear Vision Camera (RVC) on page 2-59
for more information.
If the vehicle has RVC, the
O(On/Off) button for
turning the automatic dimming feature on or off will not
be available.
Automatic Dimming Mirror Operation
Automatic dimming reduces the glare from the
headlamps of the vehicle behind you. The dimming
feature comes on and the indicator light illuminates each
time the ignition is turned to start.
Cleaning the Mirror
Do not spray glass cleaner directly on the mirror. Use a
soft towel dampened with water.
Outside Manual Mirrors
Adjust the outside mirrors to see the side of the vehicle
and have a clear view of objects behind you.
Manually fold the mirrors inward to prevent damage when
going through an automatic car wash. To fold, push the
mirror toward the vehicle. Push the mirror outward, to
return to its original position.
Using hood-mounted air deectors and add-on convex
mirror attachments could decrease mirror performance.
Outside Towing Mirrors
If the vehicle has towing mirrors, they can be adjusted
for a clearer view of the objects behind you. Manually
pull out the mirror head to extend it for better visibility
when towing a trailer.
Manually fold the mirrors forward or rearward. The
lower portion of the mirror is convex. A convex mirror’s
surface is curved to see more from the driver seat.
The convex mirror can be adjusted manually to
the driver preferred position for better vision.
The mirror may have a turn signal arrow that ashes in
the direction of the turn or lane change.
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