2015 GMC SIERRA Brake

Black plate (42,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
5-42 Instruments and Controls
This message clears itself after
several seconds. This message also
clears if you acknowledge it. After
this message clears, the TRAILER
GAIN and OUTPUT displays appear
in the DIC.
SeeDriver Information Center (DIC)
on page 5-27 and“Integrated Trailer
Brake Control System” under
Towing Equipment on page 9-78.
Vehicle Speed Messages
REDUCE SPEED FOR HILL
DESCENT CONTROL
This message displays when
attempting to enable Hill Descent
Control (HDC) when the vehicle
speed is too high. See Hill Descent
Control (HDC) on page 9-51.
Washer Fluid Messages
WASHER FLUID LOW ADD
FLUID
This message displays when the
windshield washer fluid is low. Fill
the windshield washer fluid reservoir
as soon as possible. See Engine
Compartment Overview on
page 10-5 for the location of the
windshield washer fluid reservoir.
Also, see Washer Fluid on
page 10-25 for more information.
Vehicle
Personalization
Use the audio system controls to
access the personalization menus
for customizing vehicle features.
The following are all possible
personalization features. Depending
on the vehicle, some may not be
available.
Radio Audio System Controls
1. Press the desired feature to
display a list of available
options.
2. Press to select the desired feature setting.
3. Press
oBACK on the faceplate
or the
0screen button to return
to the previous menu or exit.
Turn the vehicle to ON/RUN to
access the Settings menu, then
select SETTINGS from the Home
Page on the infotainment system
display.

Black plate (45,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
Instruments and Controls 5-45
adjusted to this level. To set the
maximum startup volume, press +
or−to increase or decrease.
Vehicle
Select and the following may
display:
.Climate and Air Quality
.Collision/Detection Systems
.Comfort and Convenience
.Lighting
.Power Door Locks
.Remote Lock, Unlock, Start
Climate and Air Quality
Select the Climate and Air Quality
menu and the following may display:
.Auto Fan Max Speed
.Auto Rear Defog
Auto Fan Max Speed
This feature will set the maximum
auto fan speed.
Select Low, Medium, or High. Auto Rear Defog
If equipped, this feature will
automatically turn on the rear
window defogger when it is cold
outside.
Select Off or On.
Collision/Detection Systems
Select the Collision/Detection
Systems menu and the following
may display:
.Alert Type
.Auto Collision Preparation
.Park Assist
Alert Type
This feature will set crash alerts to
beeps or seat vibrations. This
setting affects all crash alerts
including Forward Collision Alert,
Lane Departure Warning, and Park
Assist alerts.
Select Beeps or Safety Alert Seat. Auto Collision Preparation
This feature will turn on or off the
Forward Collision Alert feature as
well as the automatic braking
capability of the Auto Collision
Preparation feature. With the Alert
and Brake setting, both Forward
Collision Alert as well as the
automatic braking capability of the
Auto Collision Preparation feature
are available. The Alert setting
disables most automatic braking
functions of the Auto Collision
Preparation feature. Some
last-second automatic braking
capability is still provided with the
Alert setting, but it is much less
likely to be triggered by most driving
conditions. Off disables all Forward
Collision Alert and automatic
braking capabilities of the Auto
Collision Preparation feature.
Select Off, Alert and Brake, or Alert.
See
Object Detection System
Messages on page 5-35.

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 (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
{Warning
Taking 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.
{Warning
Drinking 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.
{Caution
If 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 andthen, 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 (6,1)GMC 2015i Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-8431500) - 2015 - crc - 6/20/14
9-6 Driving and Operating
If the vehicle starts to slide, follow
these suggestions:
.Ease your foot off the
accelerator pedal and steer the
way you want the vehicle to go.
The 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.
{Warning
When 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)
on page 9-51
.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.

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.