GMC 2011 Sierra User Manual
Page 354
Black plate (60,1)
GMC Sierra Owner Manual - 2011
9-60
Driving and Operating
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
the vehicle. This is the best setting
to use when plowing snow.
4
n
(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.
If the vehicle has StabiliTrak
®
,
shifting into Four-Wheel Drive
Low will turn Traction Control and
StabiliTrak off. See StabiliTrak
{
WARNING
Shifting the transfer case to
N (Neutral) can cause the vehicle
to roll even if the transmission
is in P (Park). You or someone
else could be seriously injured.
Be sure to set the parking brake
before placing the transfer case
in N (Neutral). See Parking Brake
on page 9‑69.
N (Neutral): Shift the vehicle's
transfer case to N (Neutral)
only when towing the vehicle.
See Recreational Vehicle Towing on
page 10‑103 or Towing the Vehicle
on page 10‑103 for more
information.
If the SERVICE 4 WHEEL DRIVE
message stays on, you should
take the vehicle to your dealer for
service. See “SERVICE 4 WHEEL
DRIVE message” under
Transmission Messages on
page 5‑50.
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 72 km/h (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 ON/RUN and the vehicle must be
stopped or moving less than 5 km/h
(3 mph) with the transmission in
N (Neutral). The preferred method
for shifting into Four-Wheel Drive
Low is to have the vehicle moving
1.6 to 3.2 km/h (1 to 2 mph).