2007 GMC YUKON XL transmission

DRIVE (D):This position is for normal driving.
It provides the best fuel economy for your vehicle.
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.
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.
Downshifting the transmission in slippery road
conditions could result in skidding, see Skidding
underLoss of Control on page 355
THIRD (3):This position is also used for normal
driving. However, it reduces vehicle speed
more than DRIVE (D) without using your brakes.
You can use THIRD (3) 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.SECOND (2):This position reduces vehicle speed
even more than THIRD (3) without using your
brakes. 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 select SECOND (2) and the Tow/Haul has
not been selected, the transmission will drive
in SECOND (2) 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.
If you select SECOND (2) and the Tow/Haul has
also been selected, the transmission operation will
be limited to FIRST (1) and SECOND (2) gears.
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.
FIRST (1):This position reduces vehicle speed
even more than SECOND (2) without using
your brakes. 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.
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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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You can choose among four driving settings:
2
m(Two-Wheel Drive 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.
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 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 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 your vehicle. This is
the best setting to use when plowing snow.
4
n(Four-Wheel Drive 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 Drive 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.
SeeStabiliTrak®System on page 348for
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 151.
NEUTRAL (N):Shift the vehicle’s transfer case
to NEUTRAL only when towing your vehicle.
SeeRecreational Vehicle Towing on page 401or
Towing Your Vehicle on page 400for more
information.
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Indicator lights in the button will come on to 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 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.
If the SERVICE 4 WHEEL DRIVE message stays
on, you should take your vehicle to your dealer
for service. See “SERVICE 4 WHEEL DRIVE
message” underDIC Warnings and Messages on
page 254.
Shifting Into Four-Wheel Drive High or
AUTO (Automatic Four-Wheel Drive)
Turn the knob to the Four-Wheel High or AUTO
position. This can be done at any speed,
except when shifting from Four-Wheel Drive Low,
and the indicator light will ash while shifting. It
will remain on when the shift is completed.
Shifting Into Two-Wheel Drive High
Turn the knob to the Two-Wheel High position.
This can be done at any speed, except when
shifting from Four-Wheel Drive Low.
Shifting Into Four-Wheel Drive Low
To shift to the Four-Wheel Drive 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). Turn the knob to the Four-Wheel
Drive Low position. You must wait for the
Four-Wheel Drive 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.
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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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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 151for 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 Two-Wheel
Drive High.
6. Turn the transfer case knob to NEUTRAL and
hold it 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.
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. Turn the transfer case knob to the desired
transfer case shift position (Two-Wheel
Drive High, Four-Wheel Drive High, AUTO).
After the transfer case has shifted out of
NEUTRAL the NEUTRAL light will go out.
4. Release the parking brake.
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.
5. 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.
150

CAUTION: (Continued)
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 152.
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, then you will be able to
pull the shift lever out of PARK (P).
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Shifting Out of Park (P)
Automatic Transmission
Your vehicle has an automatic transmission shift
lock control system which locks the shift lever
in PARK (P) when the ignition is in the LOCK
position. You have to fully apply your regular
brakes before you can shift from PARK (P) when
the ignition is in RUN. SeeAutomatic Transmission
Operation on page 142.
If you cannot shift out of PARK (P), ease pressure
on the shift lever and push the shift lever all the
way up into PARK (P) as you maintain brake
application. Then, move the shift lever into
the gear desired.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot
exhaust parts under your vehicle and
ignite. Do not park over papers, leaves,
dry grass, or other things that can burn.
154