2018 GMC SIERRA DENALI light

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
274 Driving and Operating .
Shifting while the vehicle is in
motion may require that
moderate force be applied to the
shift lever before 4
m can be
engaged, especially in cold
weather.
.
In extremely cold weather, it may
be necessary to slow or stop the
vehicle to shift.
.
While in 4
m , the vehicle can be
driven at any posted legal speed
limit.
Shifting In or Out of 4
nCaution
Shifting the transfer case into 4
nwhile moving at speeds faster
than 5 km/h (3 mph) may cause
premature wear to the transfer
case, and may cause the gears to
grind.
1. If possible, shift with the
vehicle moving 5 km/h (3 mph)
or less. 2. Shift the transmission into
N (Neutral).
3. Shift the transfer case shift
lever in one continuous motion.
4. Shifting with the vehicle at a
stop may be more difficult. It is
possible that the shift will not
complete and the transfer case
will remain in N (Neutral). This
is normal. To complete the
shift, with the engine running,
shift the transmission to
D (Drive) and back to
N (Neutral), and reattempt the
transfer case shift.
Shifting In or Out of N (Neutral)
1. Have the engine running.
2. Set the parking brake. Press
and hold the brake pedal. See
Parking Brake 0 281 .
3. Place the transmission into
N (Neutral).
4. Shift the transfer case lever in
one continuous motion into or
out of N (Neutral). Electronic Transfer Case
Use the transfer case knob, next to
the steering wheel, to shift into and
out of four-wheel drive for extra
traction.
All of the lights will blink on then off
momentarily when the ignition is
turned on. The light that remains on
will indicate the state of the
transfer case.
If the indicator mark on the switch
does not match up with the light
then that likely means the switch
was moved when the ignition
was off.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 275The indicator mark on the switch
must line up with the indicator light
before a shift can be commanded.
To command a shift rotate the
transfer case switch to the new
desired position. The light will blink
meaning that the shift is in progress.
When the shift is completed the new
position will be illuminated. If the
transfer case can not complete a
shift command, it will go back to its
last chosen setting.
In extreme cold weather it may be
necessary to slow or stop the
vehicle to shift from 2
m to 4
m .
Delayed shifts from 4
m to 2
m may be
experienced due to uneven tire
wear, low tire pressure, high vehicle
loading, or cold temperatures.
Caution
Shifting the transmission into gear
before the requested mode
indicator light has stopped
flashing could damage the
transfer case. The settings are:
N (Neutral) : Use only when the
vehicle needs to be towed. See
Recreational Vehicle Towing 0 430
or Towing the Vehicle 0 430 .
2
m (Two-Wheel Drive High) : Use
for driving on most streets and
highways. The front axle is not
engaged. This setting provides the
best fuel economy.
4
n (Four-Wheel Drive Low) : This
setting engages the front axle and
delivers extra torque. Choose 4
n if
driving off-road in deep sand, deep
mud, or deep snow, and while
climbing or descending steep hills.
When engaged, keep vehicle speed
below 72 km/h (45 mph).
Shifting into 4
n will turn Traction
Control and StabiliTrak off. See
Traction Control/Electronic Stability
Control 0 282 .
4
m (Four-Wheel Drive High) : Use
when extra traction is needed. The
front axle engages and helps when
driving on snowy or icy roads, when off-roading, or when plowing snow.
The vehicle can be shifted from 2
mto 4
m while the vehicle is moving.
Shifting Into 4
m Turn the knob to 4
m at any speed
up to 121 km/h (75 mph), except
from 4
n . The indicator light will flash
while shifting and will remain on the
selected setting.
Shifting Into 2
m Turn the knob to 2
m at any speed,
except when shifting from 4
n .
Shifting Into 4
n When 4
n is engaged, vehicle speed
should be kept below 72 km/h
(45 mph).
1. The ignition must be on 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).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
276 Driving and Operating 2. Turn the knob to 4
n . Wait for
the 4
n indicator light to stop
flashing before shifting the
transmission into gear.
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 see the indicator. With the
vehicle moving less than 5 km/h
(3 mph), and the transmission in
N (Neutral), attempt the shift again.
Shifting Out of 4
n1. To shift out of 4
n the vehicle
must be stopped or moving
less than 5 km/h (3 mph) with
the transmission in N (Neutral)
and the ignition in on. 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
m or 2
m .
Wait for the 4
m or 2
m indicator
light to stop flashing before
shifting the transmission
into gear.
If the transmission is in gear and/or
moving more than 5 km/h (3 mph),
the 4
m or 2
m indicator light will flash
for 30 seconds, but will not complete
the shift. With the vehicle moving
less than 5 km/h (3 mph), and the
transmission in N (Neutral), attempt
the shift again.
Shifting Into N (Neutral)
To shift:
1. Park the vehicle on a level
surface.
2. Set the parking brake and
press and hold the brake
pedal. See Parking Brake
0 281 .
3. Start the vehicle or turn the
ignition on.
4. Shift the transmission to
N (Neutral). 5. Shift the transfer case to 2
m .
6. Turn the transfer case knob
clockwise to N (Neutral) until it
stops and hold it there until the
N (Neutral) light starts blinking.
This will take at least
10 seconds. Then slowly
release the knob to the 4
n position. The N (Neutral) light
will come on when the transfer
case shift to N (Neutral) is
complete.
7. With the engine running, verify
that the transfer case is in
N (Neutral) by shifting the
transmission to R (Reverse),
then to D (Drive). There should
be no movement of the vehicle
while shifting the transmission.
8. Turn the engine off, and the
ignition to ACC/ACCESSORY.
9. Place the transmission shift
lever in P (Park). See
Recreational Vehicle Towing
0 430 .
10. Turn the ignition off.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 277Shifting Out of N (Neutral)
To shift:
1. Set the parking brake and
apply the brake pedal.
2. Turn the ignition on with the
engine off.
3. Shift the transmission to
N (Neutral).
4. Turn the transfer case knob to
2
m .
After the transfer case has
shifted out of N (Neutral), the
N (Neutral) light will go out.
5. Release the parking brake.
Caution
Shifting the transmission into gear
before the requested mode
indicator light has stopped
flashing could damage the
transfer case.
6. Start the engine and shift the
transmission to the
desired gear. Automatic Transfer Case
If equipped, use the transfer case
knob next to the steering wheel to
shift into and out of four-wheel drive.
All of the lights will blink on then off
momentarily when the ignition is
turned on. The light that remains on
will indicate the state of the
transfer case.
If the indicator mark on the switch
does not match up with the light
then that likely means the switch
was moved when the ignition
was off. The indicator mark on the switch
must line up with the indicator light
before a shift can be commanded.
To command a shift rotate the
transfer case switch to the new
desired position. The light will blink
meaning that the shift is in progress.
When the shift is completed the new
position will be illuminated. If the
transfer case can not complete a
shift command, it will go back to its
last chosen setting.
The settings are:
N (Neutral) : Use only when the
vehicle needs to be towed. See
Recreational Vehicle Towing 0 430
or Towing the Vehicle 0 430 .
2
m (Two-Wheel Drive High) : Use
for driving on most streets and
highways. The front axle is not
engaged. This setting provides the
best fuel economy.
AUTO (Automatic Four-Wheel
Drive) : Use when road surface
traction conditions are variable.
When driving in AUTO, the front
axle is engaged, and the vehicle's
power is sent to the front and rear

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
278 Driving and Operating wheels automatically based on
driving conditions. This setting
provides slightly lower fuel economy
than 2
m .
Do not use AUTO mode,
if equipped, to park on a steep
grade with poor traction such as ice,
snow, mud, or gravel. In AUTO
mode only the rear wheels 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, when
off-roading, or when plowing snow.
4
n (Four-Wheel Drive Low) : This
setting engages the front axle and
delivers extra torque. Choose 4
nwhen driving off-road in deep sand,
deep mud, or deep snow, and while
climbing or descending steep hills. Shifting into 4
n will turn Traction
Control and StabiliTrak off. See
Traction Control/Electronic Stability
Control 0 282 .
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:
1. The ignition must be on 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.
CautionShifting 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 279Shifting Out of 4
nTo shift:
1. The vehicle must be stopped or
moving less than 5 km/h
(3 mph) with the transmission
in N (Neutral) and the ignition
on. 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
m , AUTO,
or 2
m . Wait for the 4
m , AUTO,
or 2
m 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
m , AUTO, or 2
m indicator light
will flash for 30 seconds but will not
complete the shift. With the vehicle
moving less than 5 km/h (3 mph),
and the transmission in N (Neutral),
attempt the shift again.
Shifting Into N (Neutral)
To shift into N (Neutral):
1. Park the vehicle on a level
surface.
2. Set the parking brake and
press and hold the brake
pedal. See Parking Brake
0 281 .
3. Start the vehicle or turn the
ignition on.
4. Shift the transmission to
N (Neutral).
5. Shift the transfer case to 2
m . 6. Turn the transfer case knob
clockwise to N (Neutral) until it
stops and hold it there until the
N (Neutral) light starts blinking.
This will take at least
10 seconds. Then slowly
release the knob to the 4
n position. The N (Neutral) light
will come on when the transfer
case shift to N (Neutral) is
complete.
7. With the engine running, verify
that the transfer case is in
N (Neutral) by shifting the
transmission to R (Reverse),
then shift the transmission to
D (Drive). There should be no
movement of the vehicle while
shifting the transmission.
8. Turn the engine off, and the
ignition to ACC/ACCESSORY.
9. Place the transmission shift
lever in P (Park). See
Recreational Vehicle Towing
0 430 .
10. Turn the ignition to off.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
280 Driving and Operating Shifting Out of N (Neutral)
To shift out of N (Neutral):
1. Set the parking brake and
apply the brake pedal.
2. Turn the ignition on with the
engine off.
3. Shift the transmission to
N (Neutral).
4. Turn the transfer case knob to
the desired setting.
After the transfer case has
shifted out of N (Neutral), the
N (Neutral) light will go out.
5. Release the parking brake.
6. Start the engine and shift the
transmission to the
desired gear. Brakes Antilock Brake
System (ABS) This vehicle has an Antilock Brake
System (ABS), an advanced
electronic braking system that helps
prevent a braking skid.
When the vehicle begins to drive
away, ABS checks itself.
A momentary motor or clicking noise
may be heard while this test is going
on, and it may even be noticed that
the brake pedal moves a little. This
is normal.
If there is a problem with ABS, this
warning light stays on. See Antilock
Brake System (ABS) Warning Light
0 152 . If driving safely on a wet road and it
becomes necessary to slam on the
brakes and continue braking to
avoid a sudden obstacle, a
computer senses the wheels are
slowing down. If one of the wheels
is about to stop rolling, the computer
will separately work the brakes at
each wheel.
ABS can change the brake pressure
to each wheel, as required, faster
than any driver could. This can help
you steer around the obstacle while
braking hard.
As the brakes are applied, the
computer keeps receiving updates
on wheel speed and controls
braking pressure accordingly.
Remember: ABS does not change
the time needed to get a foot up to
the brake pedal or always decrease
stopping distance. If you get too
close to the vehicle in front of you,
there will not be enough time to
apply the brakes if that vehicle
suddenly slows or stops. Always
leave enough room up ahead to
stop, even with ABS.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 281Using ABS Do not pump the brakes. Just hold
the brake pedal down firmly and let
ABS work. You may hear the ABS
pump or motor operating and feel
the brake pedal pulsate. This is
normal.
Braking in Emergencies ABS allows you to steer and brake
at the same time. In many
emergencies, steering can help
more than even the very best
braking.
Parking Brake Set the parking brake by holding the
regular brake pedal down, then
pushing down the parking brake
pedal.
If the ignition is on, the brake
system warning light will come on.
See Brake System Warning Light
0 152 .
CautionDriving with the parking brake on
can overheat the brake system
and cause premature wear or
damage to brake system parts.
Make sure that the parking brake
is fully released and the brake
warning light is off before driving.
To release the parking brake, hold
the regular brake pedal down, then
push down momentarily on the
parking brake pedal until you feel
the pedal release. Slowly pull your
foot up off the parking brake pedal.
If the parking brake is not released
when you begin to drive, a DIC message will appear and a chime
will sound warning you that the
parking brake is still on.
Brake Assist The Brake Assist feature is
designed to assist the driver in
stopping or decreasing vehicle
speed in emergency driving
conditions. This feature uses the
stability system hydraulic brake
control module to supplement the
power brake system under
conditions where the driver has
quickly and forcefully applied the
brake pedal in an attempt to quickly
stop or slow down the vehicle. The
stability system hydraulic brake
control module increases brake
pressure at each corner of the
vehicle until the ABS activates.
Minor brake pedal pulsation or
pedal movement during this time is
normal and the driver should
continue to apply the brake pedal as
the driving situation dictates. The
Brake Assist feature will
automatically disengage when the