2005 GMC YUKON transmission

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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Automatic Transfer Case
For four-wheel drive vehicles with StabiliTrak®, see
StabiliTrak®System on page 4-10.
Use these buttons to shift into and out of four-wheel
drive.
You can choose among four driving settings:
AUTO 4WD (Automatic Four-Wheel Drive):This
setting is ideal for use when road surface traction
conditions are variable. When driving your vehicle in
AUTO 4WD, the front axle is engaged, but the vehicle’s
power is sent only to the rear wheels. When the
vehicle senses a loss of traction, the system will
automatically engage four-wheel drive. Driving in this
mode results in slightly lower fuel economy than
Two-Wheel High.
2
m(Two Wheel-High):This setting is used for
driving in most street and highway situations. Your front
axle is not engaged in two-wheel drive. This setting
also provides the best fuel economy.
4
m(Four Wheel-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 your vehicle.
This is the best setting to use when plowing snow.4
n(Four Wheel-Low):This setting also engages
your 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-Low if you
are driving off-road in deep sand, deep mud, deep snow,
and while climbing or descending steep hills.
StabiliTrak
®will not engage in this mode. See
StabiliTrak®System on page 4-10for more information.
{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.
NEUTRAL (N):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.
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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.
2-32

If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See
SERVICE 4WD underDriver Information Center (DIC)
on page 3-54.
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). Press and release the
Four-Wheel Low switch. 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.
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 return to the
setting last chosen.
When in Four-Wheel Low, StabiliTrak
®is automatically
disabled. For more information seeStabiliTrak®
System on page 4-10.
Shifting Out of Four Wheel-Low
To shift from Four-Wheel Low to All-Wheel Drive, 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. Press and release the all-wheel drive
button. You must wait for the All-Wheel Drive indicator
light to stop ashing and remain illuminated before
shifting your transmission into gear.
If the All-Wheel Drive button is pressed when your
vehicle is in gear and/or moving, the All-Wheel Drive
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. SeeParking Brake on
page 2-35for more information.
3. Start the vehicle or turn the ignition to RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to All-Wheel Drive.
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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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