
Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
In Brief 1-1
In Brief
Instrument Panel
Instrument Panel . . . . . . . . . . . . . . 1-2
Initial Drive Information
Remote Keyless Entry (RKE)System . . . . . . . . . . . . . . . . . . . . . . 1-4
Remote Vehicle Start . . . . . . . . . 1-5
Door Locks . . . . . . . . . . . . . . . . . . . 1-5
Windows . . . . . . . . . . . . . . . . . . . . . . 1-6
Seat Adjustment . . . . . . . . . . . . . . 1-7
Memory Features . . . . . . . . . . . . . 1-8
Heated and Cooled Front Seats . . . . . . . . . . . . . . . . . . . . . . . . 1-8
Head Restraint Adjustment . . . . 1-9
Safety Belts . . . . . . . . . . . . . . . . . . . 1-9
Passenger Sensing System . . . 1-9
Mirror Adjustment . . . . . . . . . . . . 1-10 Steering Wheel
Adjustment . . . . . . . . . . . . . . . . . 1-11
Throttle and Brake Pedal Adjustment . . . . . . . . . . . . . . . . . 1-12
Interior Lighting . . . . . . . . . . . . . . 1-12
Exterior Lighting . . . . . . . . . . . . . 1-13
Windshield Wiper/Washer . . . . 1-13
Climate Controls . . . . . . . . . . . . . 1-14
Transmission . . . . . . . . . . . . . . . . 1-15
Four-Wheel Drive . . . . . . . . . . . . 1-15
Vehicle Features
Infotainment System . . . . . . . . . 1-16
Steering Wheel Controls . . . . . 1-16
Cruise Control . . . . . . . . . . . . . . . 1-17
Driver Information Center (DIC) . . . . . . . . . . . . . . . 1-17
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . 1-18 Lane Departure
Warning (LDW) . . . . . . . . . . . . . 1-18
Rear Vision Camera (RVC) . . . . . . . . . . . . . 1-18
Parking Assist . . . . . . . . . . . . . . . 1-18
Power Outlets . . . . . . . . . . . . . . . 1-18
Universal Remote System . . . 1-19
Sunroof . . . . . . . . . . . . . . . . . . . . . . 1-19
Performance and Maintenance
Traction Control/Electronic
Stability Control . . . . . . . . . . . . 1-20
Tire Pressure Monitor . . . . . . . . 1-20
Engine Oil Life System . . . . . . 1-21
E85 or FlexFuel . . . . . . . . . . . . . . 1-21
Driving for Better Fuel Economy . . . . . . . . . . . . . . . . . . . 1-21
Roadside Assistance Program . . . . . . . . . . . . . . . . . . . . 1-22
OnStar
®. . . . . . . . . . . . . . . . . . . . . 1-22 

Black plate (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
In Brief 1-3
1.Instrument Panel Illumination
Control on page 6-6.
2. Integrated Trailer Brake Control (ITBC) System (If Equipped).
See Towing Equipment on
page 9-78.
3. Exterior Lamp Controls on
page 6-1.
Fog Lamps on page 6-5 (If
Equipped).
4. Air Vents on page 8-4.
5. Turn Signal Lever. See Turn and
Lane-Change Signals on
page 6-4.
Windshield Wiper/Washer on
page 5-3.
6. Favorite Switches (Out of View). See Steering Wheel Controls on
page 5-2.
Volume Switches (Out of View).
See Steering Wheel Controls on
page 5-2.
7. Instrument Cluster on page 5-9. 8.
Hazard Warning Flashers on
page 6-4
9. Shift Lever. See Automatic
Transmission on page 9-33.
Tow/Haul Selector Button (If
Equipped). See Tow/Haul Mode
on page 9-39.
Range Selection Mode (If
Equipped). See Manual Mode on
page 9-36.
10. Light Sensor. See Automatic
Headlamp System on
page 6-3.
11. Infotainment on page 7-1.
12. Electronic Transfer Case Control (If Equipped). See
Four-Wheel Drive on
page 9-40.
13. Parking Brake on page 9-47.
14. Data Link Connector (DLC) (Out of View). See Malfunction
Indicator Lamp on page 5-18. 15.
Cruise Control on page 9-52.
Forward Collision Alert (FCA)
System on page 9-59 (If
Equipped).
16. Steering Wheel Adjustment on
page 5-2 (Out of View).
17. Horn on page 5-3.
18. Hood Release. See Hood on
page 10-4.
19. Steering Wheel Controls on
page 5-2 (If Equipped).
Driver Information Center (DIC)
Controls. See Driver
Information Center (DIC) on
page 5-27.
20. Heated and Cooled Front
Seats on page 3-7 (If
Equipped).
21. Dual Automatic Climate Control
System on page 8-1. 

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
1-4 In Brief
22.gTraction Control/Electronic
Stability Control on page 9-49.
0Pedal Adjust Switch (If
Equipped). See Adjustable
Throttle and Brake Pedal on
page 9-23.
{Cargo Lamp on page 6-6.
XParking Assist Button (If
Equipped). See Assistance
Systems for Parking or Backing
on page 9-56.
@Lane Departure Warning
(LDW) on page 9-61 (If
Equipped).
5Hill Descent Control Switch
(If Equipped). See Hill Descent
Control (HDC) on page 9-51.
qExhaust Brake (If
Equipped). See “Exhaust
Brake” in the Duramax diesel
supplement. Auxiliary Button (If Equipped).
See
Add-On Electrical
Equipment on page 9-88.
23. USB Port. See Infotainment on
page 7-1.
24. Power Outlets on page 5-5.
25. Power Outlet (Alternating Current) (If Equipped). See
Power Outlets on page 5-5.
Initial Drive
Information
Remote Keyless Entry
(RKE) System
The RKE transmitter functions may
work from up to 60 m (197 ft) away
from the vehicle.
K:Press to unlock the driver door.
Press
Kagain within three seconds
to unlock all remaining doors. 

Black plate (21,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-21
Brake System Warning
Light
The vehicle brake system consists
of two hydraulic circuits. If one
circuit is not working, the remaining
circuit can still work to stop the
vehicle. For normal braking
performance, both circuits need to
be working.
If the warning light comes on, there
is a brake problem. Have the brake
system inspected right away.
MetricEnglish
This light should come on briefly
when the engine is started. If it does
not come on then, have it fixed so it
will be ready to warn if there is a
problem. When the ignition is on, the brake
system warning light also comes on
when the parking brake is set. The
light stays on if the parking brake
does not fully release. If it stays on
after the parking brake is fully
released, it means the vehicle has a
brake problem.
If the light comes on while driving,
pull off the road and stop carefully.
The pedal might be harder to push,
or the pedal can go closer to the
floor. It may take longer to stop.
If the light is still on, have the
vehicle towed for service. See
Towing the Vehicle on page 10-91.
{Warning
The brake system might not be
working properly if the brake
system warning light is on.
Driving with the brake system
warning light on can lead to a
crash. If the light is still on after
the vehicle has been pulled off
(Continued)
Warning (Continued)
the road and carefully stopped,
have the vehicle towed for
service.
Antilock Brake System
(ABS) Warning Light
This light comes on briefly when the
engine is started.
If the light does not come on, have it
fixed so it will be ready to warn if
there is a problem.
If the light comes on while driving,
stop as soon as it is safely possible
and turn off the vehicle. Then start
the engine again to reset the
system. If the ABS light stays on,
or comes on again while driving, the 

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-1
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . . 9-2
Defensive Driving . . . . . . . . . . . . . 9-3
Drunk Driving . . . . . . . . . . . . . . . . . 9-3
Control of a Vehicle . . . . . . . . . . . 9-3
Braking . . . . . . . . . . . . . . . . . . . . . . . 9-3
Steering . . . . . . . . . . . . . . . . . . . . . . . 9-4
Off-Road Recovery . . . . . . . . . . . . 9-5
Loss of Control . . . . . . . . . . . . . . . . 9-5
Off-Road Driving . . . . . . . . . . . . . . 9-6
Driving on Wet Roads . . . . . . . . 9-11
Hill and Mountain Roads . . . . . 9-11
Winter Driving . . . . . . . . . . . . . . . 9-12
If the Vehicle Is Stuck . . . . . . . . 9-14
Vehicle Load Limits . . . . . . . . . . 9-15
Truck-Camper LoadingInformation . . . . . . . . . . . . . . . . . 9-21
Starting and Operating
New Vehicle Break-In . . . . . . . . 9-23
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 9-23
Ignition Positions . . . . . . . . . . . . 9-24
Starting the Engine . . . . . . . . . . 9-26 Fast Idle System . . . . . . . . . . . . . 9-27
Engine Heater . . . . . . . . . . . . . . . 9-28
Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . 9-29
Shifting Into Park . . . . . . . . . . . . 9-30
Shifting out of Park . . . . . . . . . . 9-31
Parking over Things
That Burn . . . . . . . . . . . . . . . . . . 9-32
Active Fuel Management
®. . . 9-32
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 9-32
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . 9-33
Automatic Transmission
Automatic Transmission . . . . . 9-33
Manual Mode . . . . . . . . . . . . . . . . 9-36
Tow/Haul Mode . . . . . . . . . . . . . . 9-39
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . 9-40
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . 9-46
Parking Brake . . . . . . . . . . . . . . . 9-47
Brake Assist . . . . . . . . . . . . . . . . . 9-48
Hill Start Assist (HSA) . . . . . . . 9-48
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . 9-49
Hill Descent Control (HDC) . . . . . . . . . . . . . . 9-51
Locking Rear Axle . . . . . . . . . . . 9-52
Cruise Control
Cruise Control . . . . . . . . . . . . . . . 9-52
Driver Assistance Systems
Driver Assistance
Systems . . . . . . . . . . . . . . . . . . . . 9-55
Assistance Systems for Parking or Backing . . . . . . . . . 9-56
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . 9-59
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . 9-59
Lane Departure Warning (LDW) . . . . . . . . . . . . . 9-61
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . 9-63
California FuelRequirements . . . . . . . . . . . . . . 9-64
Fuels in Foreign Countries . . . 9-64
Fuel Additives . . . . . . . . . . . . . . . 9-64 

Black plate (8,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-8 Driving and Operating
cannot be seen, get out of the
vehicle and walk the hill before
driving further.
When driving on hills:
.Use a low gear and keep a firm
grip on the steering wheel.
.Maintain a slow speed.
.When possible, drive straight up
or down the hill.
.Slow down when approaching
the top of the hill.
.Use headlamps even during the
day to make the vehicle more
visible.
{Warning
Driving to the top of a hill at high
speed can cause an accident.
There could be a drop-off,
embankment, cliff, or even
another vehicle. You could be
seriously injured or killed. As you
near the top of a hill, slow down
and stay alert.
.Never go downhill forward or
backward with either the
transmission or transfer case in
N (Neutral). The brakes could
overheat and you could lose
control.
{Warning
If the vehicle has the two‐speed
automatic transfer case, shifting
the transfer case to N (Neutral)
can cause your vehicle to roll
even if the transmission is in
P (Park). This is because the
N (Neutral) position on the
transfer case overrides the
transmission. You or someone
else could be injured. If leaving
the vehicle, set the parking brake
and shift the transmission to
P (Park). Shift the transfer case to
any position but N (Neutral).
.When driving down a hill, keep
the vehicle headed straight
down. Use a low gear because
the engine will work with thebrakes to slow the vehicle and
help keep the vehicle under
control.
{Warning
Heavy braking when going down
a hill can cause your brakes to
overheat and fade. This could
cause loss of control and you or
others could be injured or killed.
Apply the brakes lightly when
descending a hill and use a low
gear to keep vehicle speed under
control.
If the vehicle stalls on a hill:
1. Apply the brakes to stop the vehicle, and then apply the
parking brake. 

Black plate (9,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-9
2. Shift into P (Park) and thenrestart the engine.
.If driving uphill when the
vehicle stalls, shift to
R (Reverse), release the
parking brake, and back
straight down.
.Never try to turn the vehicle
around. If the hill is steep
enough to stall the vehicle,
it is steep enough to cause
it to roll over.
.If you cannot make it up the
hill, back straight down
the hill.
.Never back down a hill in
N (Neutral) using only the
brake. The vehicle can roll
backward quickly and you
could lose control.
.If driving downhill when the
vehicle stalls, shift to a
lower gear, release the
parking brake, and drive
straight down the hill. 3. If the vehicle cannot be restarted
after stalling, set the parking
brake, shift into P (Park), and
turn the vehicle off.
3.1. Leave the vehicle and seek help.
3.2. Stay clear of the path the vehicle would take if it
rolled downhill.
.Avoid turns that take the vehicle
across the incline of the hill.
A hill that can be driven straight
up or down might be too steep to
drive across. Driving across an
incline puts more weight on the
downhill wheels, which could
cause a downhill slide or a
rollover.
.Surface conditions can be a
problem. Loose gravel, muddy
spots, or even wet grass can
cause the tires to slip sideways,
downhill. If the vehicle slips
sideways, it can hit something
that will trip it —a rock, a rut,
etc. —and roll over.
.Hidden obstacles can make the
steepness of the incline more
severe. If a rock is driven across
with the uphill wheels, or if the
downhill wheels drop into a rut
or depression, the vehicle can tilt
even more.
.If an incline must be driven
across, and the vehicle starts to
slide, turn downhill. This should
help straighten out the vehicle
and prevent the side slipping.
{Warning
Getting out of the vehicle on the
downhill side when stopped
across an incline is dangerous.
If the vehicle rolls over, you could
be crushed or killed. Always get
out on the uphill side of the
vehicle and stay well clear of the
rollover path. 

Black plate (25,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-25
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:
1. Brake using a firm and steadypressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting
to N (Neutral), firmly apply the
brakes and steer the vehicle to a
safe location.
3. Come to a complete stop, shift to P (Park), and turn the ignition
to LOCK/OFF. On vehicles with
an automatic transmission, the
shift lever must be in P (Park) to
turn the ignition switch to the
LOCK/OFF position. 4. Set the parking brake. See
Parking Brake on page 9-47.
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY.
{Caution
Using a tool to force the key to
turn in the ignition could cause
damage to the switch or break the
key. Use the correct key, make
sure it is all the way in, and turn it
only with your hand. If the key
cannot be turned by hand, see
your dealer. 2 (ACC/ACCESSORY):
This
position lets things like the radio
and the windshield wipers operate
while the engine is off. It also
unlocks the steering wheel. Use this
position if the vehicle must be
pushed or towed.
3 (ON/RUN): This position can be
used to operate the electrical
accessories and to display some
instrument cluster warning and
indicator lights. This position can
also be used for service and
diagnostics, and to verify the proper
operation of the malfunction
indicator lamp as may be required
for emission inspection purposes.
The switch stays in this position
when the engine is running. The
transmission is also unlocked in this
position on automatic transmission
vehicles.
If the key is left in the ACC/
ACCESSORY or ON/RUN position
with the engine off, the battery could
be drained. The vehicle may not
start if the battery is allowed to drain
for an extended period of time.