fuel GMC SIERRA 2018 Owner's Guide

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Instruments and Controls 163
Economy Trend :Shows history of
the Average Fuel Economy from the
last 50 km (30 mi). Each bar
represents about 5 km (3 mi) of
driving. During driving the bars will
shift to always reflect the most
recent distance on the right side.
Press and hold
Vto clear the graph
or press
pto reset through
the menu.
ECO Index : The bar graph
provides feedback on the efficiency
of current driving behavior. The
graph shows a value that is based
on current fuel consumption
compared to what is expected from
the vehicle with good and bad
driving habits. It also shows if the
Active Fuel Management is active
and in V4 mode, or inactive and in
V8 mode. See Active Fuel
Management 0264. Engine Hours :
Shows the total
number of hours the engine has run.
This display also shows the engine
idle hours.
Trailer Brake : On vehicles with the
Integrated Trailer Brake Control
(ITBC) system, the trailer brake
display appears in the DIC.
TRAILER GAIN shows the trailer
gain setting. This setting can be
adjusted from 0.0 to 10.0 with either
a trailer connected or disconnected.
OUTPUT shows the power output to
the trailer any time a trailer with
electric brakes is connected. Output
is displayed as a bar graph. Dashes
may appear in the OUTPUT display.
Speed Signs : Shows sign
information, which comes from a
roadway database in the onboard
navigation. Following Distance :
Used to
select the alert timing for the
Forward Collision Alert (FCA). See
Forward Collision Alert (FCA)
System 0292.
Blank Page : Shows no
information.
Transmission Fluid Temperature
Gauge : Shows the temperature of
the automatic transmission fluid in
either degrees Celsius (°C) or
degrees Fahrenheit (°F).
Off Road : Displays vehicle pitch
and roll information, road wheel
angle, and four-wheel drive (4WD)
status.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
228 Climate Controls
Dual Automatic Climate Control System
With this system the heating, cooling, and ventilation in the vehicle can be
controlled.
For an eAssist vehicle, see the Silverado/Sierra eAssist supplement.
1. Driver Temperature Control
2. A/C (Air Conditioning)
3. Air Delivery Mode Controls
4. Fan Control
5. Defrost
6. Passenger TemperatureControl 7. SYNC (Synchronized
Temperature)
8. Rear Window Defogger
9. Power Button
10. Air Recirculation
11. AUTO (Automatic Operation) Automatic Operation
The system automatically controls
the fan speed, air delivery, air
conditioning, and recirculation in
order to heat or cool the vehicle to
the desired temperature.
When the indicator light is on, the
system is in full automatic operation.
If the air delivery mode or fan
setting is manually adjusted, the
auto indicator turns off and displays
will show the selected settings.
To place the system in
automatic mode:
1. Press AUTO.
2. Set the driver and passenger temperature.
To find your comfort setting,
start with 22 °C (72 °F) and
allow the system time to
stabilize. Then adjust the
temperature as needed for best
comfort.
To improve fuel efficiency and to
cool the vehicle faster, recirculation
may be automatically selected in
warm weather.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
234 Driving and Operating
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . 235
Defensive Driving . . . . . . . . . . . . . 236
Drunk Driving . . . . . . . . . . . . . . . . . 236
Control of a Vehicle . . . . . . . . . . . 236
Braking . . . . . . . . . . . . . . . . . . . . . . . 236
Steering . . . . . . . . . . . . . . . . . . . . . . 237
Off-Road Recovery . . . . . . . . . . . 238
Loss of Control . . . . . . . . . . . . . . . 238
Off-Road Driving . . . . . . . . . . . . . 239
Driving on Wet Roads . . . . . . . . 244
Hill and Mountain Roads . . . . . 245
Winter Driving . . . . . . . . . . . . . . . . 245
If the Vehicle Is Stuck . . . . . . . . 247
Vehicle Load Limits . . . . . . . . . . . 248
Truck-Camper LoadingInformation . . . . . . . . . . . . . . . . . . 253
Starting and Operating
New Vehicle Break-In . . . . . . . . . 255
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 256
Ignition Positions . . . . . . . . . . . . . 256
Starting the Engine . . . . . . . . . . . 258
Fast Idle System . . . . . . . . . . . . . 259 Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . . 260
Engine Coolant Heater . . . . . . . 260
Shifting Into Park . . . . . . . . . . . . . 262
Shifting out of Park . . . . . . . . . . . 263
Parking over Things That Burn . . . . . . . . . . . . . . . . . . . 264
Active Fuel Management . . . . . 264
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 264
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . . 265
Automatic Transmission
Automatic Transmission . . . . . . 265
Manual Mode . . . . . . . . . . . . . . . . . 268
Tow/Haul Mode . . . . . . . . . . . . . . . 271
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . 272
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . . 280
Parking Brake . . . . . . . . . . . . . . . . 281
Brake Assist . . . . . . . . . . . . . . . . . . 281
Hill Start Assist (HSA) . . . . . . . . 282
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . . 282 Hill Descent Control (HDC) . . . 284
Locking Rear Axle . . . . . . . . . . . . 285
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . 285
Driver Assistance Systems
Driver Assistance Systems . . . 288
Assistance Systems for
Parking or Backing . . . . . . . . . . 289
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . 292
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . 292
Forward Automatic Braking (FAB) . . . . . . . . . . . . . . . 294
Lane Departure Warning (LDW) (2500/3500
Series) . . . . . . . . . . . . . . . . . . . . . . 295
Lane Keep Assist (LKA) (1500 Series) . . . . . . . . . . . . . . . . . . . . . . 297
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 299
California FuelRequirements . . . . . . . . . . . . . . . 300
Fuels in Foreign Countries . . . 300
Fuel Additives . . . . . . . . . . . . . . . . 300
E85 or FlexFuel . . . . . . . . . . . . . . 300
Filling the Tank . . . . . . . . . . . . . . . 301

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 235
Filling a Portable FuelContainer . . . . . . . . . . . . . . . . . . . 303
Trailer Towing
General TowingInformation . . . . . . . . . . . . . . . . . . 303
Driving Characteristics and Towing Tips . . . . . . . . . . . . . . . . . 303
Trailer Towing . . . . . . . . . . . . . . . . 307
Towing Equipment . . . . . . . . . . . . 325
Trailer Sway Control (TSC) . . . 334
Conversions and Add-Ons
Add-On Electrical Equipment . . . . . . . . . . . . . . . . . . 336
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . . . . . . 337
Pickup Conversion to Chassis Cab . . . . . . . . . . . . . . . . 340
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, keep
your eyes on the road, keep your
hands on the steering wheel, and
focus your attention on driving.
. 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 239
.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.
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 seat 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.
. Know the local laws that apply to
off-road driving.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
240 Driving and Operating
To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower air
dam, if equipped. 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.
Loading the Vehicle for
Off-Road Driving
{Warning
.Unsecured cargo on the
load floor can be tossed
about when driving over
rough terrain. You or your
(Continued)
Warning (Continued)
passengers can be struck
by flying objects. Secure the
cargo properly.
. Keep cargo in the cargo
area as far forward and as
low as possible. The
heaviest things should be
on the floor, forward of the
rear axle.
. Heavy loads on the roof
raise the vehicle's center of
gravity, making it more likely
to roll over. You can be
seriously or fatally injured if
the vehicle rolls over. Put
heavy loads inside the
cargo area, not on the roof.
For more information about loading
the vehicle, see Vehicle Load Limits
0 248 andTires 0389.
Environmental Concerns
.
Always use established trails,
roads, and areas that have been
set aside for public off-road
recreational driving and obey all
posted regulations.
. Do not damage shrubs, flowers,
trees, or grasses or disturb
wildlife.
. Do not park over things that
burn. See Parking over Things
That Burn 0264.
Driving on Hills
Driving safely on hills requires good
judgment and an understanding of
what the vehicle can and cannot do.
{Warning
Many hills are simply too steep
for any vehicle. Driving up hills
can cause the vehicle to stall.
Driving down hills can cause loss
of control. Driving across hills can
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
244 Driving and Operating
After Off-Road Driving
Remove any brush or debris that
has collected on the underbody or
chassis, or under the hood. These
accumulations can be a fire hazard.
After operation in mud or sand,
have the brake linings cleaned and
checked. These substances can
cause glazing and uneven braking.
Check the body structure, driveline,
steering, suspension, wheels, tires,
and exhaust system for damage and
check the fuel lines and cooling
system for any leakage.
More frequent maintenance service
is required. See theMaintenance
Schedule 0448.
Driving on Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep-standing or flowing water.
{Warning
Wet brakes can cause crashes.
They might not work as well in a
quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause the
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under the vehicle's
tires so they actually ride on the
water. This can happen if the road is
wet enough and you are going fast
enough. When the vehicle is
hydroplaning, it has little or no
contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.
Allow extra following distance.
. Pass with caution.
. Keep windshield wiping
equipment in good shape.
. Keep the windshield washer fluid
reservoir filled.
. Have good tires with proper
tread depth. See Tires0389.
. Turn off cruise control.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
246 Driving and Operating
.Allow greater following distance
and watch for slippery spots. Icy
patches can occur on otherwise
clear roads in shaded areas.
The surface of a curve or an
overpass can remain icy when
the surrounding roads are clear.
Avoid sudden steering
maneuvers and braking while
on ice.
. Turn off cruise control.
Blizzard Conditions
Stop the vehicle in a safe place and
signal for help. Stay with the vehicle
unless there is help nearby.
If possible, use Roadside
Assistance. See Roadside
Assistance Program 0469. To get
help and keep everyone in the
vehicle safe:
. Turn on the hazard warning
flashers.
. Tie a red cloth to an outside
mirror.
{Warning
Snow can trap engine exhaust
under the vehicle. This may
cause exhaust gases to get
inside. Engine exhaust contains
carbon monoxide (CO), which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
If the vehicle is stuck in snow:
. Clear snow from the base of
the vehicle, especially any
blocking the exhaust pipe.
. Open a window about 5 cm
(2 in) on the vehicle side
that is away from the wind,
to bring in fresh air.
. Fully open the air outlets on
or under the instrument
panel.
. Adjust the climate control
system to circulate the air
inside the vehicle and set
(Continued)
Warning (Continued)
the fan speed to the highest
setting. See“Climate
Control Systems.”
For more information about CO,
see Engine Exhaust 0264.
To save fuel, run the engine for
short periods to warm the vehicle
and then shut the engine off and
partially close the window. Moving
about to keep warm also helps.
If it takes time for help to arrive,
when running the engine, push the
accelerator pedal slightly so the
engine runs faster than the idle
speed. This keeps the battery
charged to restart the vehicle and to
signal for help with the headlamps.
Do this as little as possible, to
save fuel.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 251
of the driver, passengers, and
cargo should never exceed the
vehicle's capacity weight.
Certification/Tire Label
A vehicle-specific Certification/
Tire label is label is attached to
the center pillar (B-pillar). The
label may show the size of the
vehicle's original tires and the
inflation pressures needed to
obtain the gross weight capacity
of the vehicle. This is called
Gross Vehicle Weight
Rating (GVWR). The GVWRincludes the weight of the
vehicle, all occupants, fuel, and
cargo.
The Certification/Tire label also
may show the maximum weights
for the front and rear axles,
called Gross Axle Weight
Rating (GAWR). To determine
the actual loads on the front and
rear axles, weigh the vehicle at
a weigh station. Your dealer can
help with this. Be sure to spread
the load equally on both sides of
the centerline.
The Certification/Tire label also
contains important information
about the Front Axle Reserve
Capacity. See
Adding a Snow
Plow or Similar Equipment
0 337.
{Warning
In the case of a sudden stop
or collision, things carried in
the bed of your truck could
shift forward and come into
the passenger area, injuring
you and others. If you put
things in the bed of your truck,
you should make sure they
are properly secured.
Caution
Overloading the vehicle may
cause damage. Repairs would not
be covered by the vehicle
warranty. Do not overload the
vehicle.
Using heavier suspension
components to get added
durability might not change the
weight ratings. Ask your dealer
to help load the vehicle the
right way.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
258 Driving and Operating
The switch stays in this position
when the engine is running. The
transmission is also unlocked in this
position.
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.
3 (START) :This is the position that
starts the engine. When the engine
starts, release the key. The ignition
switch returns to ON/RUN for
driving.
A warning tone will sound when the
driver door is opened and the
ignition is in ACC/ACCESSORY or
LOCK/OFF, and the key is in the
ignition.
Starting the Engine
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
For an eAssist vehicle, see the
Silverado/Sierra eAssist
supplement.
Caution
If you add electrical parts or
accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See Add-On Electrical Equipment
0 336.
Caution
If the steering wheel is turned
until it reaches the end of its
travel, and is held in that position
while starting the vehicle, damage
may occur to the power steering
system and there may be loss of
power steering assist.
Move the shift lever to P (Park) or
N (Neutral). To restart the engine
when the vehicle is already moving,
use N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you
could damage the transmission.
Shift to P (Park) only when the
vehicle is stopped.
Starting Procedure
1. Turn the ignition key to START. When the engine starts, let go
of the key. The idle speed will
go down as the engine gets
warm. Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently to allow the
oil to warm up and lubricate all
moving parts.
When the low fuel warning light
is on and the FUEL LEVEL
LOW message is displayed in
the Driver Information Center
(DIC), hold the ignition switch
in the START position to
continue engine cranking.