
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Climate Controls 2511. Open the lower glove box door
completely.
2. Remove the four screws from
around the lower glove box.
The door does not need to be
removed to access the screws.
3. Close the lower glove box door
and pull it from its frame to
remove the entire unit. 4. Release the two tabs holding
the service door. Open the
service door and remove the
old filter.
5. Install the new air filter.
6. Close the service door and
secure the tabs.
7. Reverse the steps to reinstall
the glove box.
See your dealer if additional
assistance is needed. Service All vehicles have a label underhood
that identifies the refrigerant used in
the vehicle. The refrigerant system
should only be serviced by trained
and certified technicians. The air
conditioning evaporator should
never be repaired or replaced by
one from a salvage vehicle.
It should only be replaced by a new
evaporator to ensure proper and
safe operation.
During service, all refrigerants
should be reclaimed with proper
equipment. Venting refrigerants
directly to the atmosphere is harmful
to the environment and may also
create unsafe conditions based on
inhalation, combustion, frostbite,
or other health-based concerns.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Driving and Operating 257The vehicle may straighten out.
Be ready for a second skid if it
occurs.
.
Slow down and adjust your
driving according to weather
conditions. Stopping distance
can be longer and vehicle
control can be affected when
traction is reduced by water,
snow, ice, gravel, or other
material on the road. Learn to
recognize warning clues — such
as enough water, ice, or packed
snow on the road to make a
mirrored surface — and slow
down when you have any doubt.
.
Try to avoid sudden steering,
acceleration, or braking,
including reducing vehicle speed
by shifting to a lower gear. Any
sudden changes could cause
the tires to slide.
Remember: Antilock brakes help
avoid only the braking skid.
Off-Road Driving Four-wheel-drive vehicles can be
used for off-road driving. Vehicles
without four-wheel drive and vehicles not equipped with All
Terrain (AT) or On-Off Road (OOR)
tires must not be driven off-road
except on a level, solid surface. For
contact information about the
original equipment tires, see the
warranty manual.
One of the best ways for successful
off-road driving is to control the
speed.
{ WarningWhen driving off-road, bouncing
and quick changes in direction
can easily throw you out of
position. This could cause you to
lose control and crash. You and
your passengers should always
wear safety belts.
Before Driving Off-Road
.
Have all necessary maintenance
and service work completed.
.
Fuel the vehicle, fill fluid levels,
and check inflation pressure in
all tires, including the spare,
if equipped. .
Read all the information about
four-wheel-drive vehicles in this
manual.
.
Remove any underbody air
deflector, if equipped. Re-attach
the air deflector after off-road
driving.
.
See Hill Descent Control (HDC)
0 301
.
Know the local laws that apply to
off-road driving.
To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower air
dam. However, driving without the
air dam reduces fuel economy.
Caution
Operating the vehicle for
extended periods without the front
fascia lower air dam installed can
cause improper airflow to the
engine. Reattach the front fascia
air dam after off-road driving.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
284 Driving and Operating To rock the vehicle back and forth to
get out of snow, ice, or sand without
damaging the transmission, see If
the Vehicle Is Stuck 0 264 .
N : In this position, the engine does
not connect with the wheels. To
restart when you are already
moving, use N (Neutral) only. Also,
use N (Neutral) when the vehicle is
being towed.
{ WarningShifting into a drive gear while the
engine is running at high speed is
dangerous. Unless your foot is
firmly on the brake pedal, the
vehicle could move very rapidly.
You could lose control and hit
people or objects. Do not shift
into a drive gear while the engine
is running at high speed. CautionShifting out of P (Park) or
N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.
D : This position is for normal
driving. It provides the best fuel
economy. If you need more power
for passing, and you are:
.
Going less than about 55 km/h
(35 mph), push the accelerator
pedal about halfway down.
.
Going about 55 km/h (35 mph) or
more, push the accelerator all
the way down.
By doing this, the vehicle shifts
down to the next gear and has
more power.
Use D (Drive) and Tow/Haul Mode
when towing a trailer, carrying a
heavy load, driving on steep hills, or driving off-road. Shift the
transmission to a lower gear
selection if the transmission shifts
too often.
Downshifting the transmission in
slippery road conditions could result
in skidding. See “ Skidding ” under
Loss of Control 0 256 .
The vehicle has a shift stabilization
feature that adjusts the transmission
shifting to the current driving
conditions in order to reduce rapid
upshifts and downshifts. This shift
stabilization feature is designed to
determine, before making an
upshift, if the engine is able to
maintain vehicle speed by analyzing
things such as vehicle speed,
throttle position, and vehicle load.
If the shift stabilization feature
determines that a current vehicle
speed cannot be maintained, the
transmission does not upshift and
instead holds the current gear.
In some cases, this could appear to
be a delayed shift, however the
transmission is operating normally.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Driving and Operating 285The transmission uses adaptive
shift controls. The adaptive shift
control process continually
compares key shift parameters to
pre-programmed ideal shifts stored
in the transmission ’ s computer. The
transmission constantly makes
adjustments to improve vehicle
performance according to how the
vehicle is being used, such as with
a heavy load or when the
temperature changes. During this
adaptive shift control process,
shifting might feel different as the
transmission determines the best
settings.
When temperatures are very cold,
the transmission's gear shifting
could be delayed providing more
stable shifts until the engine warms
up. Shifts could be more noticeable
with a cold transmission. This
difference in shifting is normal.
L : This position allows selection of
a range of gears appropriate for
current driving conditions.
If equipped, see “ Range Selection
Mode ” under Manual Mode 0 286 . CautionSpinning the tires or holding the
vehicle in one place on a hill
using only the accelerator pedal
may damage the transmission.
The repair will not be covered by
the vehicle warranty. If the vehicle
is stuck, do not spin the tires.
When stopping on a hill, use the
brakes to hold the vehicle in
place.
Normal Mode Grade Braking If equipped with a gasoline engine
and an automatic transmission,
Normal Mode Grade Braking is
enabled when the vehicle is started,
but is not enabled in Range
Selection Mode. It assists in
maintaining desired vehicle speeds
when driving on downhill grades by
using the engine and transmission
to slow the vehicle. The first time
the system engages for each
ignition key cycle, a DIC message
will be displayed. See Transmission
Messages 0 164 . To disable or enable Normal Mode
Grade Braking within the current
ignition key cycle, press and hold
the Tow/Haul button for
five seconds. When the button is
released, the requested mode
change is made. A DIC message
displays. See Transmission
Messages 0 164 .
For other forms of grade braking,
see Tow/Haul Mode 0 288 and
Cruise Control 0 302 .
Kickdown Mode If equipped, the accelerator pedal
provides an additional downshift
after pressing through the kickdown
feature.
It requires extra pedal pressure near
the end of its travel to engage.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Driving and Operating 305Erasing Speed Memory
The cruise control set speed is
erased from memory if
5 is pressed
or the ignition is turned off.
Driver Assistance
Systems This vehicle may have features that
work together to help avoid crashes
or reduce crash damage while
driving, backing, and parking. Read
this entire section before using
these systems.
{ WarningDo not rely on the Driver
Assistance Systems. These
systems do not replace the need
for paying attention and driving
safely. You may not hear or feel
alerts or warnings provided by
these systems. Failure to use
proper care when driving may
result in injury, death, or vehicle
damage. See Defensive Driving
0 254 .
Under many conditions, these
systems will not:
(Continued) Warning (Continued) .
Detect children,
pedestrians, bicyclists,
or animals.
.
Detect vehicles or objects
outside the area monitored
by the system.
.
Work at all driving speeds.
.
Warn you or provide you
with enough time to avoid a
crash.
.
Work under poor visibility or
bad weather conditions.
.
Work if the detection sensor
is not cleaned or is covered
by ice, snow, mud, or dirt.
.
Work if the detection sensor
is covered up, such as with
a sticker, magnet, or metal
plate.
.
Work if the area surrounding
the detection sensor is
damaged or not properly
repaired.
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Driving and Operating 309FCA can be disabled with either the
FCA steering wheel control or,
if equipped, through vehicle
personalization. See “ Collision/
Detection Systems ” under Vehicle
Personalization 0 167 .
Detecting the Vehicle Ahead
FCA warnings will not occur unless
the FCA system detects a vehicle
ahead. When a vehicle is detected,
the vehicle ahead indicator will
display green. Vehicles may not be
detected on curves, highway exit
ramps, or hills, due to poor visibility;
or if a vehicle ahead is partially
blocked by pedestrians or other
objects. FCA will not detect another
vehicle ahead until it is completely
in the driving lane. { WarningFCA does not provide a warning
to help avoid a crash, unless it
detects a vehicle. FCA may not
detect a vehicle ahead if the FCA
sensor is blocked by dirt, snow,
or ice, or if the windshield is
damaged. It may also not detect a
vehicle on winding or hilly roads,
or in conditions that can limit
visibility such as fog, rain,
or snow, or if the headlamps or
windshield are not cleaned or in
proper condition. Keep the
windshield, headlamps, and FCA
sensors clean and in good repair. Collision Alert
When your vehicle approaches
another detected vehicle too rapidly,
the red FCA display will flash on the
windshield. Also, eight rapid
high-pitched beeps will sound from
the front, or both sides of the Safety
Alert Seat will pulse five times.
When this Collision Alert occurs, the
brake system may prepare for driver
braking to occur more rapidly which
can cause a brief, mild deceleration.
Continue to apply the brake pedal
as needed. Cruise control may be
disengaged when the Collision Alert
occurs.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
312 Driving and Operating Warning (Continued)flow of traffic. If this occurs, take
your foot off the brake pedal and
then apply the brakes as needed.
FAB and IBA can be disabled
through vehicle personalization. See
“ Collision/Detection Systems ” under
Vehicle Personalization 0 167 .
{ WarningUsing FAB or IBA while towing a
trailer could cause you to lose
control of the vehicle and crash.
Turn the system to Alert or Off
when towing a trailer.
Lane Departure Warning
(LDW) (2500/3500 Series) If equipped, LDW may help avoid
crashes due to unintentional lane
departures. It may provide an alert if
the vehicle is crossing a lane
marking without using a turn signal
in that direction. LDW uses a camera sensor to detect the lane
markings at speeds of 56 km/h
(35 mph) or greater.
{ WarningThe LDW system does not steer
the vehicle. The LDW system
may not:
.
Provide enough time to
avoid a crash.
.
Detect lane markings under
poor weather or visibility
conditions. This can occur if
the windshield or
headlamps are blocked by
dirt, snow, or ice; if they are
not in proper condition; or if
the sun shines directly into
the camera.
.
Detect road edges.
.
Detect lanes on winding or
hilly roads.
If LDW only detects lane
markings on one side of the road,
it will only warn you when
(Continued) Warning (Continued) departing the lane on the side
where it has detected a lane
marking. Always keep your
attention on the road and
maintain proper vehicle position
within the lane, or vehicle
damage, injury, or death could
occur. Always keep the
windshield, headlamps, and
camera sensors clean and in
good repair. Do not use LDW in
bad weather conditions.
How the System Works The LDW camera sensor is on the
windshield ahead of the rearview
mirror.
To turn LDW on and off, press
@ on
the center stack. The control
indicator will light when LDW is on.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
314 Driving and Operating Warning (Continued).
Detect lanes on winding or
hilly roads.
If LKA only detects lane markings
on one side of the road, it will
only assist or provide an LDW
alert when approaching the lane
on the side where it has detected
a lane marking. Even with LKA
and LDW, you must steer the
vehicle. Always keep your
attention on the road and
maintain proper vehicle position
within the lane, or vehicle
damage, injury, or death could
occur. Always keep the
windshield, headlamps, and
camera sensors clean and in
good repair. Do not use LKA in
bad weather conditions. { WarningUsing LKA while towing a trailer
or on slippery roads could cause
loss of control of the vehicle and
a crash. Turn the system off.
How the System Works The LKA camera sensor is on the
windshield ahead of the rearview
mirror.
To turn LKA on and off, press
Aon the center stack.
When on,
A is green if LKA is
available to assist and provide LDW
alerts. It may assist by gently
turning the steering wheel and
display
A as amber if the vehicle
approaches a detected lane marking
without using a turn signal in that
direction. It may also provide an
LDW alert by flashing
A amber
as the lane marking is crossed.
Additionally, there may be three
beeps, or the driver seat may pulse three times, on the right or left,
depending on the lane departure
direction.
Take Steering
The LKA system does not
continuously steer the vehicle.
If LKA does not detect active driver
steering, an alert, chime, or DIC
message may be provided. Move
the steering wheel to dismiss.
When the System Does Not
Seem to Work Properly The system performance may be
affected by:
.
Close vehicles ahead.
.
Sudden lighting changes, such
as when driving through tunnels.
.
Banked roads.
.
Roads with poor lane markings,
such as two-lane roads.
If the LKA system is not functioning
properly when lane markings are
clearly visible, cleaning the
windshield may help.