2003 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 won’t shift intorst
gear until the vehicle is going slowly enough.
Notice:If your wheels won’t turn, don’t try to drive.
This might happen if you were stuck in very deep
sand or mud or were up against a solid object. You
could damage your transmission. Also, if you
stop when going uphill, don’t hold your vehicle there
with only the accelerator pedal. This could overheat
and damage the transmission. Use your brakes
or shift into PARK (P) to hold your vehicle in
position on a hill.
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 4-61for more information.
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2003 - Yukon/Yukon XL

When tow/haul mode is
selected the tow/haul
indicator light will
illuminate.
The tow/haul mode also interacts with the Autoride™
feature, if your vehicle is so equipped, to enhance
the ride when trailering or with a loaded vehicle. See
Autoride™on page 4-60.
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. 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. See
the appropriate text for the transfer case in your
vehicle.
Notice:Driving in the 4-WHEEL HIGH (4HI) or
4-WHEEL LOW (4LO) positions for a long time on
dry or wet pavement could shorten the life of
your vehicle’s drivetrain.
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
{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. See″Parking Brake″in the
Index.
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g(4LO):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 4LO if you are driving off-road in
deep sand, deep mud, deep snow and 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. See″Parking Brake″in the
Index.
NEUTRAL:Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-55orTowing
Your Vehicle on page 4-54for more information.Indicator lights in the switches 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 willash 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 3-53.
Shifting into 4HI or AUTO 4WD
Press and release the 4 hi or AUTO 4WD switch. This
can be done at any speed (except when shifting
from 4LO), and the indicator light willash while shifting.
It will remain illuminated when the shift is completed.
Shifting into 2HI
Press and release the 2 hi switch. This can be done at
any speed (except when shifting from 4LO).
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Shifting into 4LO
To shift to the 4 lo position, the ignition must be in RUN
and the vehicle must be stopped or moving less than
3 mph (4.8 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the 4 lo switch. You must wait for the
4LO indicator light to stopashing and remain
illuminated before shifting your transmission in gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stoppedflashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stopflashing before shifting
your transmission into gear.
It is typical for your vehicle to exhibit signicant
engagment noise and bump when shifting between
4LO and 4HI ranges or from NEUTRAL with the engine
running.
If the 4 lo switch is pressed when your vehicle is in gear
and/or moving, the 4LO indicator light willash for
30 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds
the transfer case will return to the setting last chosen.
Shifting Out of 4LO
To shift from 4LO to 4HI, AUTO 4WD or 2HI your
vehicle must be stopped or moving less than 3 mph
(4.8 km/h) with the transmission in NEUTRAL (N) and
the ignition in RUN. The preferred method for shifting out
of 4LO is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the 4HI,
AUTO 4WD or 2HI switch. You must wait for the 4HI,
AUTO 4WD or 2HI indicator light to stopashing
and remain illuminated before shifting your transmission
into gear.
Notice:Shifting the transmission into gear before
the 4LO indicator light has stoppedflashing
could damage the transfer case. To help avoid
damaging your vehicle, always wait for the
4LO indicator light to stopflashing before shifting
your transmission into gear.
It is typical for your vehicle to exhibit signicant
engagment noise and bump when shifting between
4LO and 4HI ranges or from NEUTRAL with the engine
running.
If the 4HI, AUTO 4WD or 2HI switch is pressed when
your vehicle is in gear and/or moving, the 4HI,
AUTO 4WD or 2HI indicator light willash for
30 seconds but will not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N).
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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. Connect the vehicle to the towing vehicle.
5. Put the transmission in NEUTRAL (N).
6. Shift the transfer case to 2HI.
7. Simultaneously press and hold the 2HI and 4LO
buttons for 10 seconds. The red NEUTRAL light
will come on when the transfer case shift to
NEUTRAL is complete.
8. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
9. Turn the ignition off.
10. Place the transmission shift lever in PARK (P).
11. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
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 (2HI, 4HI, AUTO 4WD OR 4 LO).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. You may 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.
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All-Wheel Drive with Stabilitrak®
With this feature, engine power is sent to all four wheels
all the time.
This 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 adjust itself as needed for
road conditions.
The transfer case buttons are located to the left of the
instrument panel cluster.
Use these switches to shift into and out of four-wheel
drive.You can choose among three driving settings:d(Stabilitrak®):This button is used with the
Stabilitrak®system and is also used to shift the transfer
case into Neutral. For more information on using
Stabilitrak
®seeStabilitrak®System on page 4-12.
f(All-Wheel Drive):This setting delivers power to
all four wheels as needed depending on road and driving
conditions.
g(4LO):This setting delivers extra torque. You may
never need this setting. It sends maximum power to
all four wheels. You might choose 4LO if you are driving
off-road in deep sand, deep mud, deep snow and
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. See″Parking Brake″in the
Index.
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2003 - Yukon/Yukon XL

NEUTRAL:Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-55orTowing
Your Vehicle on page 4-54for more information.
Indicator lights in the switches 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 willash 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 underDriver Information Center (DIC)
on page 3-53.
Shifting into 4LO
To shift to the 4LO position, the ignition must be in RUN
and the vehicle must be stopped or moving less than
3 mph (4.8 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the 4LO switch. You must wait for the
4LO indicator light to stopashing and remain
illuminated before shifting your transmission in gear.Notice:Shifting the transmission into gear before
the 4LO indicator light has stoppedflashing could
damage the transfer case. To help avoid damaging
your vehicle, always wait for the 4LO indicator light
to stopflashing before shifting your transmission
into gear.
If the 4LO switch is pressed when your vehicle is in
gear and/or moving, the 4LO indicator light willash for
30 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and the
transmission is in NEUTRAL (N). After 30 seconds
the transfer case will return to the setting last chosen.
When in 4LO, the vehicle stability is disabled. For more
information seeStabilitrak
®System on page 4-12.
Shifting Out of 4LO
To shift from 4LO to AWD your vehicle must be stopped
or moving less than 3 mph (4.8 km/h) with the
transmission in NEUTRAL (N) and the ignition in RUN.
The preferred method for shifting out of 4LO is to have
your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h). Press
and release the AWD switch. You must wait for the AWD
indicator light to stopashing and remain illuminated
before shifting your transmission into gear.
If the AWD switch is pressed when your vehicle is in
gear and/or moving, the AWD indicator light willash for
30 seconds but will not complete the shift unless your
vehicle is moving less than 3 mph (4.8 km/h) and
the transmission is in NEUTRAL (N).
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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. Connect the vehicle to the towing vehicle.
5. Put the transmission in NEUTRAL (N).
6. Shift the transfer case to AWD.
7. Simultaneously press and hold the Stabilitrak
®and
4LO buttons for 10 seconds. The red NEUTRAL
light will come on when the transfer case shift
to NEUTRAL is complete.8. Shift the transmission to REVERSE (R) for one
second, then shift the transmission to DRIVE (D)
for one second.
9. Turn the ignition to LOCK.
10. Place the transmission shift lever in PARK (P).
11. Release the parking brake prior to towing.
Shifting Out of NEUTRAL
To shift out of NEUTRAL:
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 4LO).
4. After the transfer case has shifted out of NEUTRAL
the red light will go out.
5. You may start the engine and shift the transmission
to the desired position.
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