GMC SIERRA 2007 Owner's Manual
Page 151 of 680
Shifting In or Out of Four-Wheel-Drive Low
Notice:Shifting the transfer case into
Four-Wheel-Drive Low while moving at speeds
faster than 3 mph (5 km/h) may cause
premature wear to the transfer case, and may
cause the gears to grind. To avoid causing
premature wear, and grinding the gears, do not
shift the transfer case into Four-Wheel-Drive
Low while the vehicle is moving faster than
3 mph (5 km/h).
Shifting into Four-Wheel-Drive Low should be
done, if possible, with the vehicle at a slight roll,
3 mph (5 km/h) or less.
Shift the transmission into NEUTRAL (N).
{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 162.
Shifting into Four-Wheel-Drive Low with the
vehicle at a stop may be more difficult. You
may be unable to complete the shift to
Four-Wheel-Drive Low, and will end up in
NEUTRAL. This is normal, and is a function of
the gear teeth aligning in your transfer
case. When this happens, make sure the
engine is on, shift your transmission
momentarily to drive and back to NEUTRAL,
and then complete the shift.
Shift the transfer case shift lever in
one continuous motion into the
Four-Wheel-Drive Low position.
When Four-Wheel-Drive Low do not drive
faster than 45 mph. This will reduce wear
and extend the life of your transfer case.
Shifting In or Out of NEUTRAL
1. With the vehicle running and the engine at an
idle set the parking brake.
2. Place the transmission into NEUTRAL (N).
Shift the transfer case in one continuous motion
into or out of the NEUTRAL position.
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Electronic Transfer Case
The transfer case knob
is located next to the
steering column.
Use the dial to shift into and out of
four-wheel drive.
Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2m4m4nN
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeRecreational Vehicle Towing on page 439
Towing Your Vehicle on page 439
You can choose among four driving settings:
Indicator lights in the dial show which setting you
are in. The indicator lights will come on brie y
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 ashes while shifting the transfer case and
remains 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.
2
m(Two-Wheel-Drive High):This setting is
used for driving in most street and highway
situations. The front axle is not engaged in
Two-Wheel Drive. This setting also provides the
best fuel economy.
4
m(Four-Wheel-Drive High):Use the
Four-Wheel-Drive High position when extra traction
is needed, such as on snowy or icy roads or in
most off-road situations. This setting also engages
the front axle to help drive your vehicle. This is
the best setting to use when plowing snow.
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4n(Four-Wheel-Drive Low):This setting also
engages the 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 while driving
off-road in deep sand, deep mud, deep snow, and
while climbing or descending steep hills.
StabiliTrak
®will not engage in this mode.
{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 162.
N (NEUTRAL):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 439or
Towing Your Vehicle on page 439for more
information.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 279.
Shifting Into Two-Wheel-Drive High
Turn the knob to the Two-Wheel-Drive High
position. This can be done at any speed, except
when shifting from Four-Wheel-Drive Low.
See Shifting Out of Four-Wheel-Drive Low for
more information.
Shifting Into Four-Wheel Drive Low
When Four-Wheel-Drive Low is engaged, vehicle
speed should be kept below 45 mph. Extended
high-speed operation in Four-Wheel-Drive Low may
damage or shorten the life of the drivetrain.
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-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 Low position.
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