2015 GMC SIERRA DENALI Owners Manual

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
8-4 Climate Controls Caution (Continued)not be covered by the vehicle
warranty. Do not clear the inside
rear window with sharp objects.
Heated Mirror: If equipped with
heated outside rearview mirrors, the
mirrors heat to help clear fog or frost
from the surface of the mirror when
the rear window defog button is
pressed. See Heated Mirrors on
page 2-17 .
Sensors The solar sensor, located in the
defrost grille in the middle of the
instrument panel, monitors the solar
heat. Do not cover the solar sensor
or the system will not work properly.
There is also an exterior
temperature sensor behind the front
grille. This sensor reads the outside
air temperature and helps maintain
the temperature inside the vehicle.
Any cover on the front of the vehicle
including a snow plow, could cause
a false reading in the displayed
temperature.
The climate control system uses the
information from these sensors to
maintain comfort settings by
adjusting the outlet temperature, fan
speed, and the air delivery mode.
The system may also supply cooler
air to the side of the vehicle facing
the sun. The recirculation mode will
also be used as needed to maintain
cool outlet temperatures. Air Vents Use the air vents in the center and
on the side of the instrument panel
to direct airflow. Use the
thumbwheels near the air vents to
open or close off the airflow.
Air vents blow warm air on the side
windows in cold weather. If Floor,
Defog, or Defrost modes are
selected, a small amount of air will
come from the vents close to the
window. If the airflow is shut off
using the thumbwheels, warm air
will be directed to the other
instrument panel vents. This is
normal operation.
Use the thumbwheels to turn vent
airflow on or off based on the mode
selected.
Operation Tips .
Clear away any ice, snow,
or leaves from air inlets at the
base of the windshield that could
block the flow of air into the
vehicle.

Black plate (5,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Climate Controls 8-5.
Keep the path under the front
seats clear of objects to help
circulate the air inside of the
vehicle more effectively. .
Use of non-GM approved hood
deflectors can adversely affect
the performance of the system.
Check with your dealer before
adding equipment to the outside
of the vehicle.
Maintenance Passenger Compartment
Air Filter The filter reduces the dust, pollen,
and other airborne irritants from
outside air that is pulled into the
vehicle.
The filter should be replaced as part
of routine scheduled maintenance.
See Maintenance Schedule on
page 11-3 . To find out what type of
filter to use, see Maintenance
Replacement Parts on page 11-14 . 1. 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.

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 (2,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-2 Driving and Operating E85 or FlexFuel . . . . . . . . . . . . . . 9-65
Filling the Tank . . . . . . . . . . . . . . 9-66
Filling a Portable Fuel
Container . . . . . . . . . . . . . . . . . . . 9-67
Trailer Towing General Towing
Information . . . . . . . . . . . . . . . . . 9-68
Driving Characteristics and
Towing Tips . . . . . . . . . . . . . . . . 9-68
Trailer Towing . . . . . . . . . . . . . . . . 9-71
Towing Equipment . . . . . . . . . . . 9-78
Trailer Sway
Control (TSC) . . . . . . . . . . . . . . 9-87
Conversions and Add-Ons Add-On Electrical
Equipment . . . . . . . . . . . . . . . . . 9-88
Adding a Snow Plow or
Similar Equipment . . . . . . . . . . 9-88
Pickup Conversion to
Chassis Cab . . . . . . . . . . . . . . . 9-92 Driving Information Distracted Driving Distraction comes in many forms
and can take your focus from the
task of driving. Exercise good
judgment and do not let other
activities divert your attention away
from the road. Many local
governments have enacted laws
regarding driver distraction. Become
familiar with the local laws in
your area.
To avoid distracted driving, always
keep your eyes on the road, hands
on the wheel, and mind on the drive. .
Do not use a phone in
demanding driving situations.
Use a hands-free method to
place or receive necessary
phone calls. .
Watch the road. Do not read,
take notes, or look up
information on phones or other
electronic devices. .
Designate a front seat
passenger to handle potential
distractions. .
Become familiar with vehicle
features before driving, such as
programming favorite radio
stations and adjusting climate
control and seat settings.
Program all trip information into
any navigation device prior to
driving. .
Wait until the vehicle is parked
to retrieve items that have fallen
to the floor. .
Stop or park the vehicle to tend
to children. .
Keep pets in an appropriate
carrier or restraint. .
Avoid stressful conversations
while driving, whether with a
passenger or on a cell phone.

Black plate (3,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Driving and Operating 9-3
{ WarningTaking your eyes off the road too
long or too often could cause a
crash resulting in injury or death.
Focus your attention on driving.
Refer to the infotainment section for
more information on using that
system and the navigation system,
if equipped, including pairing and
using a cell phone.
Defensive Driving Defensive driving means “ always
expect the unexpected. ” The first
step in driving defensively is to wear
the safety belt. See Safety Belts on
page 3-10 ..
Assume that other road users
(pedestrians, bicyclists, and
other drivers) are going to be
careless and make mistakes.
Anticipate what they might do
and be ready. .
Allow enough following distance
between you and the driver in
front of you. .
Focus on the task of driving.
Drunk Driving Death and injury associated with
drinking and driving is a global
tragedy.
{ WarningDrinking and then driving is very
dangerous. Your reflexes,
perceptions, attentiveness, and
judgment can be affected by even
a small amount of alcohol. You
can have a serious — or even
fatal — collision if you drive after
drinking.
Do not drink and drive or ride with
a driver who has been drinking.
Ride home in a cab; or if you are
with a group, designate a driver
who will not drink. Control of a Vehicle Braking, steering, and accelerating
are important factors in helping to
control a vehicle while driving.
Braking Braking action involves perception
time and reaction time. Deciding to
push the brake pedal is perception
time. Actually doing it is
reaction time.
Average driver reaction time is
about three-quarters of a second. In
that time, a vehicle moving at
100 km/h (60 mph) travels 20 m
(66 ft), which could be a lot of
distance in an emergency.
Helpful braking tips to keep in mind
include: .
Keep enough distance between
you and the vehicle in front
of you. .
Avoid needless heavy braking. .
Keep pace with traffic.

Black plate (4,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-4 Driving and Operating If the engine ever stops while the
vehicle is being driven, brake
normally but do not pump the
brakes. Doing so could make the
pedal harder to push down. If the
engine stops, there will be some
power brake assist but it will be
used when the brake is applied.
Once the power assist is used up, it
can take longer to stop and the
brake pedal will be harder to push.
Steering Electric Power Steering (1500
Series) If the vehicle has electric power
steering, it does not have power
steering fluid. Regular maintenance
is not required.
If power steering assist is lost due
to a system malfunction, the vehicle
can be steered, but may require
increased effort. See your dealer if
there is a problem. If the steering wheel is turned until it
reaches the end of its travel, and is
held in that position for an extended
period of time, power steering assist
may be reduced.
If the steering assist is used for an
extended period of time, power
assist may be reduced.
Normal use of the power steering
assist should return when the
system cools down.
See specific vehicle steering
messages under Steering System
Messages on page 5-38 .
Hydraulic Power Steering
(2500/3500 Series) If the vehicle has hydraulic power
steering, it may require
maintenance. See Power Steering
Fluid (1500 Series) on page 10-24
or Power Steering Fluid (2500/3500
Series) on page 10-24 . If power steering assist is lost
because the engine stops or a
system malfunctions, the vehicle
can be steered but may require
increased effort.
See your dealer if there is a
problem.
{ CautionIf the steering wheel is turned
until it reaches the end of its
travel, and is held in that position
for more than 15 seconds,
damage may occur to the power
steering system and there may be
loss of power steering assist.
Curve Tips .
Take curves at a reasonable
speed. .
Reduce speed before entering a
curve. .
Maintain a reasonable steady
speed through the curve.

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.