engine GMC YUKON 2005 User Guide

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).
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.
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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 4-67for more information.
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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 4-66.
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 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 for extended periods of time.The transfer case buttons
are located to the left of
the instrument panel
cluster.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.
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Indicator lights in the button show which setting you are
in. The indicator lights will come on briey when you
turn on the ignition and one will stay on. If the lights do
not come on, you should take your vehicle to your
dealer for service. An indicator light will ash while
shifting the transfer case. It will remain illuminated when
the shift is complete. If for some reason the transfer
case cannot make a requested shift, it will return to the
last chosen setting.
If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See “Service
4WD message” underDriver Information Center (DIC)
on page 3-54.
Shifting Into Four-Wheel High or AUTO
4WD (Automatic Four Wheel Drive)
Press and release the Four-Wheel High or automatic
four wheel drive button. This can be done at any speed,
except when shifting from Four Wheel-Low, and the
indicator light will ash while shifting. It will remain on
when the shift is completed.
Shifting Into Two-Wheel High
Press and release the Two-Wheel High button. This can
be done at any speed, except when shifting from
Four-Wheel Low.
Shifting Into Four-Wheel Low
To shift to the Four-Wheel Low position, the ignition
must be in RUN and the vehicle must be stopped
or moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N). The preferred method for
shifting into four-wheel low is to have your vehicle
moving 1 to 2 mph (1.6 to 3.2 km/h). Press and release
the Four-Wheel Low button. You must wait for the
four-wheel low indicator light to stop ashing and remain
on before shifting your transmission in 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 Low and Four-Wheel High ranges or from
NEUTRAL with the engine running.
If the Four-Wheel Low button is pressed when your
vehicle is in gear and/or moving, the Four-Wheel 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 High mode.
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Shifting Out of Four-Wheel Low
To shift from Four-Wheel Low to Four-Wheel High, AUTO
4WD or Two-Wheel 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 Low is to have your
vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press and
release the Four-Wheel High, AUTO 4WD or Two-Wheel
High button. You must wait for the Four-Wheel High,
AUTO 4WD or Two-Wheel 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 Low and Four-Wheel High ranges or from
NEUTRAL with the engine running.
If the Four-Wheel High, AUTO 4WD or Two Wheel High
switch is pressed when your vehicle is in gear and/or
moving, the Four-Wheel High, AUTO 4WD or Two-Wheel
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).
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it will
not roll.
2. Set the parking brake.
3. Start the vehicle or turn the ignition to RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to Two-Wheel High.
6. Simultaneously press and hold the Two-Wheel High
and Four-Wheel Low buttons for 10 seconds. The
NEUTRAL light will come on when the transfer case
shift to NEUTRAL is complete.
7. If the engine is running, verify that the transmission
is in NEUTRAL (N) by shifting the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Turn the ignition to ACCESSORY, which will turn
the engine off.
9. Place the transmission shift lever in PARK (P).
10. Turn the ignition to LOCK.
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Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (Two-Wheel High, Four-Wheel High, AUTO
4WD, or Four-Wheel Low).
4. After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.
5. Release the parking brake.
6. Start the engine and shift the transmission to the
desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to
enter the shift protection mode. This will protect the
transfer case from possible damage and will only
allow the transfer case to respond to one shift per
10 seconds. The transfer case may stay in this
mode for up to three minutes.
All-Wheel Drive with StabiliTrak®
If your vehicle has this system, you will see the buttons
shown below. With this system, engine power is sent
to all four wheels when you select the AWD button.
The transfer case buttons
are located to the left of
the instrument panel
cluster. Use these buttons
to shift between the
various modes of
four-wheel drive.
All-wheel drive is like four-wheel drive, but there is
no separate lever or switch to engage or disengage
the front axle. It is fully automatic, and when combined
with StabiliTrak
®, the all-wheel drive system adjusts
itself as needed for road conditions.
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The three modes you can choose between are:
d(StabiliTrak®):This button is used to enable or
disable the StabiliTrak®and is also used to shift the
transfer case into Neutral (N). For more information on
using StabiliTrak
®, seeStabiliTrak®System on
page 4-10.
f(All-Wheel Drive):This button allows the transfer
case to distribute power to all four wheels as needed
depending on road and driving conditions.
4
n(4LO):This button allows the transfer case to
deliver extra torque to the wheels, and provides for
precise control of wheel speed by engine braking. You
may never need this setting. It sends maximum power to
all four wheels. You might choose four-wheel low if you
are driving off-road in deep sand, deep mud, deep snow,
and while climbing or descending steep hills.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-35.
N (Neutral):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-62orTowing
Your Vehicle on page 4-62for more information.
Indicator lights in the buttons show which mode you are
in. The indicator lights will come on briey when you
turn on the ignition and one will stay on. If the lights do
not come on, you should take your vehicle to your
dealer for service. An indicator light will ash while the
transfer case is shifting. It will remain on when the
shift is complete. If for some reason the transfer case
cannot make a requested shift, it will return to the
last chosen setting.
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6. Simultaneously press and hold the StabiliTrak®and
four-wheel low buttons for 10 seconds. The red
NEUTRAL light will come on when the transfer case
shift to NEUTRAL is complete.
7. If the engine is running, verify that the transmission
is in NEUTRAL (N) by shifting the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Place the transmission shift lever in PARK (P).
9. Turn the ignition to LOCK.Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to RUN with the engine off.
3. Press the button for the desired transfer case shift
position (All-Wheel Drive or Four-Wheel Low).
4. After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.
5. Release the parking brake.
6. Start the engine and shift the transmission to the
desired position.
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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, see
Towing a Trailer on page 4-67.1. 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).
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Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in
PARK (P) with the parking brake rmly set.
If you have four-wheel drive and 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.
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
your vehicle with the engine running unless
you have to.If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is rmly set before you leave it. After you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK (P) without rst pulling it
toward you. If you can, it means that the shift lever was
not fully locked into PARK (P).
Torque Lock
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may nd it difficult to pull the
shift lever out of PARK (P). This is called “torque
lock.” To prevent torque lock, set the parking brake and
then shift into PARK (P) properly before you leave
the driver’s seat. To nd out how, seeShifting Into
Park (P) on page 2-36.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission, so
you can pull the shift lever out of PARK (P).
2-37