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Black plate (43,1)
GMC Sierra Denali Owner Manual (GMNA Localizing-U.S/Canada/Mexico-
7299750) - 2015 - CRC - 6/9/14
Driving and Operating
9-43
will hold the vehicle from sliding
when parked. If parking on a steep
grade, use 4
m
to keep all four
wheels engaged.
4
m
(Four-Wheel Drive High):
Use
this position when extra traction is
needed, such as when driving on
snowy or icy roads, off-roading,
or plowing snow.
4
n
(Four-Wheel Drive Low):
This
setting engages the front axle and
delivers extra torque. Choose 4
n
when driving off-road in deep sand,
deep mud, or deep snow, and while
climbing or descending steep hills.
Shifting into Four-Wheel Drive Low
will turn Traction Control and
StabiliTrak off. See
Electronic Stability Control on
page 9-48
.
Shifting Into 4
m
or AUTO
Turn the knob to the 4
m
or AUTO
position at any speed, except from
4
n
. The indicator light will flash
while shifting and will remain on
when the shift is completed.
Shifting Into 2
m
Turn the knob to 2
m
at any speed,
except when shifting from 4
n
. The
indicator light will flash while shifting
and will remain on when the shift is
completed.
Shifting Into 4
n
When 4
n
is engaged, keep vehicle
speed below 72 km/h (45 mph).
To shift to 4
n
:
1. 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). It is best for the
vehicle to be moving
1.6 to 3.2 km/h (1 to 2 mph).
2. Turn the knob to 4
n
. Wait for the
4
n
indicator light to stop flashing
before shifting the transmission
into gear.
{
Caution
Shifting the transmission into gear
before the requested mode
indicator light has stopped
flashing could damage the
transfer case.
If the transmission is in gear and/or
moving more than 5 km/h (3 mph),
the 4
n
indicator light will flash for
30 seconds and not complete the
shift. After 30 seconds the transfer
case will shift to 4
m
. Turn the knob
to 4
m
to display the indicator. With
the vehicle moving less than 5 km/h
(3 mph), and the transmission in
N (Neutral), attempt the shift again.