2015 GMC SIERRA DENALI ABS

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
iv Introduction
Danger, Warnings, and
Cautions Warning messages found on vehicle
labels and in this manual describe
hazards and what to do to avoid or
reduce them.
{ DangerDanger indicates a hazard with a
high level of risk which will result
in serious injury or death.
{ Warning
Warning indicates a hazard that
could result in injury or death.
{ Caution
Caution indicates a hazard that
could result in property or vehicle
damage. A circle with a slash through it is a
safety symbol which means “ Do
Not, ” “ Do not do this, ” or “ Do not let
this happen. ”
Symbols The vehicle has components and
labels that use symbols instead of
text. Symbols are shown along with
the text describing the operation or
information relating to a specific
component, control, message,
gauge, or indicator.
M : This symbol is shown when
you need to see your owner manual
for additional instructions or
information.
* : This symbol is shown when
you need to see a service manual
for additional instructions or
information. Vehicle Symbol Chart
Here are some additional symbols
that may be found on the vehicle
and what they mean. For more
information on the symbol, refer to
the Index.
0 : Adjustable Pedals
9 : Airbag Readiness Light
! : Antilock Brake System (ABS)
g : Audio Steering Wheel Controls
or OnStar ®
(if equipped)
$ : Brake System Warning Light
" : Charging System
I : Cruise Control
B : Engine Coolant Temperature
O : Exterior Lamps
# : Fog Lamps
. : Fuel Gauge
+ : Fuses
3 : Headlamp High/Low-Beam
Changer
( : Heated Steering Wheel

Black plate (1,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-1
Instruments and
Controls Controls Steering Wheel Adjustment . . . 5-2
Steering Wheel Controls . . . . . . 5-2
Heated Steering Wheel . . . . . . . 5-3
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . 5-3
Windshield Wiper/Washer . . . . . 5-3
Compass . . . . . . . . . . . . . . . . . . . . . 5-4
Clock . . . . . . . . . . . . . . . . . . . . . . . . . 5-4
Power Outlets . . . . . . . . . . . . . . . . . 5-5
Warning Lights, Gauges, and
Indicators Warning Lights, Gauges, and
Indicators . . . . . . . . . . . . . . . . . . . . 5-8
Instrument Cluster . . . . . . . . . . . . 5-9
Speedometer . . . . . . . . . . . . . . . . 5-11
Odometer . . . . . . . . . . . . . . . . . . . . 5-11
Trip Odometer . . . . . . . . . . . . . . . 5-11
Tachometer . . . . . . . . . . . . . . . . . . 5-11
Fuel Gauge . . . . . . . . . . . . . . . . . . 5-12
Engine Oil Pressure
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-12
Engine Coolant Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-13 Transmission Temperature
Gauge . . . . . . . . . . . . . . . . . . . . . . 5-14
Voltmeter Gauge . . . . . . . . . . . . . 5-15
Safety Belt Reminders . . . . . . . 5-15
Airbag Readiness Light . . . . . . 5-16
Passenger Airbag Status
Indicator . . . . . . . . . . . . . . . . . . . . 5-17
Charging System Light . . . . . . 5-18
Malfunction
Indicator Lamp . . . . . . . . . . . . . 5-18
Brake System Warning
Light . . . . . . . . . . . . . . . . . . . . . . . 5-21
Antilock Brake System (ABS)
Warning Light . . . . . . . . . . . . . . 5-21
Four-Wheel-Drive Light . . . . . . 5-22
Tow/Haul Mode Light . . . . . . . . 5-22
Hill Descent Control Light . . . . 5-22
Lane Departure Warning
(LDW) Light . . . . . . . . . . . . . . . . 5-22
Vehicle Ahead Indicator . . . . . . 5-23
Traction Off Light . . . . . . . . . . . . 5-23
StabiliTrak ®
OFF Light . . . . . . . 5-23
Traction Control System
(TCS)/StabiliTrak ®
Light . . . . 5-24
Engine Coolant Temperature
Warning Light . . . . . . . . . . . . . . 5-24
Tire Pressure Light . . . . . . . . . . 5-25
Engine Oil Pressure Light . . . . 5-25
Low Fuel Warning Light . . . . . . 5-25 Security Light . . . . . . . . . . . . . . . . 5-26
High-Beam On Light . . . . . . . . . 5-26
Front Fog Lamp Light . . . . . . . . 5-26
Lamps On Reminder . . . . . . . . . 5-26
Cruise Control Light . . . . . . . . . 5-27
Door Ajar Light . . . . . . . . . . . . . . 5-27
Information Displays Driver Information
Center (DIC) . . . . . . . . . . . . . . . 5-27
Vehicle Messages Vehicle Messages . . . . . . . . . . . 5-31
Battery Voltage and Charging
Messages . . . . . . . . . . . . . . . . . . 5-31
Brake System Messages . . . . 5-32
Compass Messages . . . . . . . . . 5-32
Door Ajar Messages . . . . . . . . . 5-33
Engine Cooling System
Messages . . . . . . . . . . . . . . . . . . 5-33
Engine Oil Messages . . . . . . . . 5-34
Engine Power Messages . . . . 5-34
Fuel System Messages . . . . . . 5-35
Key and Lock Messages . . . . . 5-35
Lamp Messages . . . . . . . . . . . . . 5-35
Object Detection System
Messages . . . . . . . . . . . . . . . . . . 5-35
Ride Control System
Messages . . . . . . . . . . . . . . . . . . 5-36

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.
Metric English
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 (22,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-22 Instruments and Controls vehicle needs service. A chime may
also sound when the light comes on
steady.
If the ABS light is the only light on,
the vehicle has regular brakes, but
the antilock brakes are not
functioning.
If both the ABS and the brake
system warning light are on, the
vehicle's antilock brakes are not
functioning and there is a problem
with the regular brakes. See your
dealer for service.
See Brake System Warning Light on
page 5-21 and Brake System
Messages on page 5-32 .
Four-Wheel-Drive Light The four-wheel-drive light comes on
when the transfer case is shifted
into four-wheel drive and the front
axle engages. LO or HI will also be
next to this light when the vehicle is
in four-wheel low or four-wheel high.
Some delay between the shifting
and the light coming on is normal.
See Four-Wheel Drive on
page 9-40 .
Tow/Haul Mode Light
For vehicles with the Tow/Haul
Mode feature, this light comes on
when the Tow/Haul Mode has been
activated.
See Tow/Haul Mode on page 9-39 .Hill Descent Control Light
If equipped, the Hill Descent Control
light comes on when the system is
ready for use. When the light
flashes, the system is active.
See Hill Descent Control (HDC) on
page 9-51 .
Lane Departure Warning
(LDW) Light
This light is green if LDW is on and
ready to operate.

Black plate (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
8-6 Climate Controls
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.

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 Loading
Information . . . . . . . . . . . . . . . . . 9-21
Starting and Operating New Vehicle Break-In . . . . . . . . 9-23
Adjustable Throttle and Brake
Pedal . . . . . . . . . . . . . . . . . . . . . . . 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 Brake
System (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 Fuel
Requirements . . . . . . . . . . . . . . 9-64
Fuels in Foreign Countries . . . 9-64
Fuel Additives . . . . . . . . . . . . . . . 9-64

Black plate (5,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-5.
Wait until the vehicle is out of
the curve before accelerating
gently into the straightaway.
Steering in Emergencies .
There are some situations when
steering around a problem may
be more effective than braking. .
Holding both sides of the
steering wheel allows you to turn
180 degrees without removing
a hand. .
Antilock Brake System (ABS)
allows steering while braking. Off-Road Recovery
The vehicle's right wheels can drop
off the edge of a road onto the
shoulder while driving. Follow
these tips:
1. Ease off the accelerator and
then, if there is nothing in the
way, steer the vehicle so that it
straddles the edge of the
pavement.
2. Turn the steering wheel about
one-eighth of a turn, until the
right front tire contacts the
pavement edge. 3. Turn the steering wheel to go
straight down the roadway.
Loss of Control Skidding There are three types of skids that
correspond to the vehicle's three
control systems: .
Braking Skid — wheels are not
rolling. .
Steering or Cornering Skid —
too much speed or steering in a
curve causes tires to slip and
lose cornering force. .
Acceleration Skid — too much
throttle causes the driving
wheels to spin.
Defensive drivers avoid most skids
by taking reasonable care suited to
existing conditions, and by not
overdriving those conditions. But
skids are always possible.

Black plate (12,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-12 Driving and Operating .
Check all fluid levels and brakes,
tires, cooling system, and
transmission. .
Shift to a lower gear when going
down steep or long hills.
{ WarningUsing the brakes to slow the
vehicle on a long downhill slope
can cause brake overheating, can
reduce brake performance, and
could result in a loss of braking.
Shift the transmission to a lower
gear to let the engine assist the
brakes on a steep downhill slope.
{ Warning
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. This can cause
overheating of the brakes and
(Continued) Warning (Continued) loss of steering. Always have the
engine running and the vehicle
in gear. .
Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane. .
Be alert on top of hills;
something could be in your lane
(stalled car, accident). .
Pay attention to special road
signs (falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.
Winter Driving Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or grip. Wet ice can occur at about 0°C
(32°F) when freezing rain begins to
fall, resulting in even less traction.
Avoid driving on wet ice or in
freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.
Traction Control should be turned
on. See Traction Control/Electronic
Stability Control on page 9-49 .
The Antilock Brake System (ABS)
improves vehicle stability during
hard stops on slippery roads, but
apply the brakes sooner than when
on dry pavement. See Antilock
Brake System (ABS) on page 9-46 .
Allow greater following distance on
any slippery road and watch for
slippery spots. Icy patches can
occur on otherwise clear roads in
shaded areas. The surface of a