engine GMC YUKON XL 2007 User Guide

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.
B (ACCESSORY):This position lets you use
things like the radio and the windshield wipers
when the engine is off.
Notice:Lengthy operation of features such as
the radio in the accessory ignition position
and the RUN position may drain the battery and
prevent your vehicle from starting. Do not
operate your vehicle in the accessory ignition
position for a long period of time.
C (RUN):This is the position for driving. It is the
position the switch returns to after the engine
starts, and you release the key.
D (START):This position starts the engine.
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Retained Accessory Power (RAP)
Your vehicle has a Retained Accessory Power
(RAP) feature which will allow certain features on
your vehicle to continue to work up to 10 minutes
after the ignition key is turned to LOCK.
The radio, power windows, and if the vehicle
has these features, the sunroof and OnStar
®
System, will work when the ignition key is in
RUN or ACCESSORY. Once the key is turned
from RUN to LOCK, these features will continue
to work for up to 10 minutes or until a door is
opened.
Starting the Engine
Move your shift lever to PARK (P) or
NEUTRAL (N). Your engine will not start in
any other position — that is a safety feature.
To restart when you are already moving, use
NEUTRAL (N) only.
Notice:Do not try to shift to PARK (P) if
your vehicle is moving. If you do, you could
damage the transmission. Shift to PARK (P)
only when your vehicle is stopped.1. With your foot off the accelerator pedal, turn
the ignition key to START. When the engine
starts, let go of the key. The idle speed will go
down as your engine gets warm.
Your vehicle has a Computer-Controlled
Cranking System. This feature assists in
starting the engine and protects the electrical
system. If the ignition key is turned to the
START position, and then released when the
engine begins cranking, the engine will continue
cranking until the vehicle starts or until it
exceeds the maximum cranking time allowed,
approximately 15 seconds to prevent cranking
motor damage. To prevent gear damage, this
system also prevents cranking if the engine is
already running. The engine cranking can be
stopped by turning the ignition switch to the
ACCESSORY or LOCK position.
Notice:Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can
overheat and damage the cranking motor and
drain the battery. Waiting about 15 seconds
between each try, to allow the cranking motor to
cool down, will prevent damage due to
overheating.
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2. If the engine does not start within 10 seconds,
push the accelerator pedal all the way to the
oor, while you hold the ignition key in
START. When the engine starts, let go of the
key and let up on the accelerator pedal.
Wait about 15 seconds between each try.
When starting your engine in very cold weather
(below 0°F or−18°C), do this:
1. With your foot off the accelerator pedal, turn
the ignition key to START and hold it there up
to 15 seconds. When the engine starts, let
go of the key.
2. If your engine still will not start, or starts but
then stops, it could be ooded with too much
gasoline. Try pushing your accelerator
pedal all the way to the oor and holding it
there as you hold the key in START for about
three seconds.When the engine starts, let go of the key and
accelerator. If the vehicle starts briey but then
stops again, do the same thing, but this time
keep the pedal down for ve or six seconds.
This clears the extra gasoline from the engine.
Notice:Your engine is designed to work with
the electronics in your vehicle. If you add
electrical parts or accessories, you could
change the way the engine operates. Before
adding electrical equipment, check with
your dealer. If you do not, your engine might
not perform properly. Any resulting damage
would not be covered by your vehicle’s
warranty.
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Adjustable Throttle and Brake Pedal
If your vehicle has this feature, you can change
the position of the throttle and brake pedals.
The switch used to
adjust the pedals is
located on the center
console below the
climate control system.
Press the arrow at the bottom of the switch to
move the pedals closer to your body. Press
the arrow at the top of the switch to move the
pedals away from your body.
This feature is designed for shorter drivers, since
the pedals can not move farther away from
the standard position, but can move toward the
driver for better pedal reach.No adjustment to the pedals can be made when
the vehicle is in REVERSE (R) or while using
the cruise control.
Your vehicle may have a memory function which
allows pedal settings to be saved and recalled.
SeeMemory Seat, Mirrors, and Pedals on
page 13for more information.
Engine Coolant Heater
Your vehicle may have an engine coolant heater.
In very cold weather, 0°F (−18°C) or colder,
the engine coolant heater can help. You will get
easier starting and better fuel economy during
engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle.
At temperatures above 32°F (0°C), use of the
coolant heater is not required. Your vehicle may
also have an internal thermostat in the plug end of
the cord. This will prevent operation of the engine
coolant heater when the temperature is at or above
0°F (−18°C) as noted on the cord.
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To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical
cord. The cord is located on the driver’s
side of the engine compartment, near
the power steering uid reservoir.
3. Plug the cord into a normal, grounded
110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded
outlet could cause an electrical shock.
Also, the wrong kind of extension cord
could overheat and cause a re. 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.
How long should you keep the coolant heater
plugged in? The answer depends on the outside
temperature, the kind of oil you have, and some
other things. Instead of trying to list everything here,
we ask that you contact your dealer in the area
where you will be parking your vehicle. The dealer
can give you the best advice for that particular area.
Displacement on Demand™ (DoD™)
Your vehicle’s V8 engine may have Displacement
on Demand™ (DoD™). This system allows the
engine to operate on either all or half of its
cylinders, depending on your 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 your 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.
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Automatic Transmission Operation
There are several different positions for the
shift lever.
Your vehicle has an automatic transmission with
an electronic shift position indicator within the
instrument panel cluster. This display will show the
position anytime the shift lever is 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. 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 152.If
you are pulling a trailer, seeTowing a
Trailer on page 405.
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{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 152.
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 388.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.
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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.
When temperatures are very cold, the Hydra-Matic
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.
The transmission torque converter clutch operation
is restricted during cold operation. When the
startup transmission temperature is approximately
64°F (18° C) your torque converter clutch will
temporarily not operate. Once the transmission
temperature rises above 68° F (20° C), normal
operation will resume.Tow/Haul Mode
Your 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 405for more
information.
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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. See
Autoride
®on page 405.
Four-Wheel Drive
If your vehicle has four-wheel drive, you can send
your engine’s driving power to all four wheels
for extra traction. 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.
Front Axle Locking Feature
The front axle locks and unlocks automatically
when you shift the transfer case. Some delay for
the axle to lock or unlock is normal.
Automatic Transfer Case
The transfer case knob
is located to the left of
the instrument panel
cluster.
Your vehicle has Four Wheel Drive with
StabiliTrak
®. For information on StabiliTrak®,
seeStabiliTrak®System on page 348.
Use this knob to shift into and out of four-wheel
drive.
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It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting
between Four-Wheel Drive Low and Four-Wheel
Drive High ranges or from NEUTRAL with the
engine running.
If the knob is turned to the Four-Wheel Low
position when your vehicle is in gear and/or
moving, the Four-Wheel Drive Low indicator light
will ash for 30 seconds and not complete the
shift unless your vehicle is moving less than
3 mph (5 km/h) and the transmission is in
NEUTRAL (N). After 30 seconds the transfer
case will shift to Four-Wheel Drive High mode.
Shifting Out of Four-Wheel Drive Low
To shift from Four-Wheel Drive Low to Four-Wheel
Drive High, AUTO or Two-Wheel Drive High,
your vehicle must be stopped or moving less
than 3 mph (5 km/h) with the transmission
in NEUTRAL (N) and the ignition in RUN. The
preferred method for shifting out of Four-Wheel
Drive Low is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Turn the knob to the
Four-Wheel Drive High, AUTO or Two-Wheel
Drive High position.You must wait for the Four-Wheel Drive High,
AUTO or Two-Wheel Drive High indicator light to
stop ashing and remain on before shifting
your transmission into gear.
Notice:Shifting the transmission into gear
before the Four-Wheel Low indicator light has
stopped ashing could damage the transfer
case. To help avoid damaging your vehicle,
always wait for the Four-Wheel Low indicator
light to stop ashing before shifting the
transmission into gear.
It is typical for your vehicle to exhibit signicant
engagement noise and bump when shifting
between Four-Wheel Drive Low and Four-Wheel
Drive High ranges or from NEUTRAL with the
engine running.
If the knob is turned to the Four-Wheel Drive High,
AUTO or Two-Wheel Drive High switch position
when your vehicle is in gear and/or moving,
the Four-Wheel Drive High, AUTO or Two-Wheel
Drive High indicator light will ash for 30 seconds
but will not complete the shift unless your
vehicle is moving less than 3 mph (5 km/h) and
the transmission is in NEUTRAL (N).
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