2018 GMC SIERRA maint

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
ContentsIntroduction . . . . . . . . . . . . . . . . . . . . . . 2
In Brief . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Keys, Doors, and Windows . . . . . 34
Seats and Restraints . . . . . . . . . . . 57
Storage . . . . . . . . . . . . . . . . . . . . . . . 124
Instruments and Controls . . . . . . 128
Lighting . . . . . . . . . . . . . . . . . . . . . . . 176
Infotainment System . . . . . . . . . . 186
Climate Controls . . . . . . . . . . . . . . 224
Driving and Operating . . . . . . . . . 234
Vehicle Care . . . . . . . . . . . . . . . . . . 341
Service and Maintenance . . . . . 446
Technical Data . . . . . . . . . . . . . . . . 460
Customer Information . . . . . . . . . 465
Reporting Safety Defects . . . . . . 476
OnStar . . . . . . . . . . . . . . . . . . . . . . . . 479
Index . . . . . . . . . . . . . . . . . . . . 491

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
In Brief 5
In Brief
Instrument Panel
Instrument Panel . . . . . . . . . . . . . . . . 6
Initial Drive Information
Initial Drive Information . . . . . . . . . . 8
Remote Keyless Entry (RKE)System . . . . . . . . . . . . . . . . . . . . . . . . 8
Remote Vehicle Start . . . . . . . . . . . 9
Door Locks . . . . . . . . . . . . . . . . . . . . . 9
Windows . . . . . . . . . . . . . . . . . . . . . . . 10
Seat Adjustment . . . . . . . . . . . . . . . 11
Memory Features . . . . . . . . . . . . . . 13
Heated and Ventilated Seats . . . 13
Head Restraint Adjustment . . . . 14
Seat Belts . . . . . . . . . . . . . . . . . . . . . 14
Passenger Sensing System . . . 14
Mirror Adjustment . . . . . . . . . . . . . . 15
Steering Wheel Adjustment . . . . 16
Throttle and Brake Pedal Adjustment . . . . . . . . . . . . . . . . . . . 17
Interior Lighting . . . . . . . . . . . . . . . . 17
Exterior Lighting . . . . . . . . . . . . . . . 18
Windshield Wiper/Washer . . . . . . 19
Climate Controls . . . . . . . . . . . . . . . 20
Transmission . . . . . . . . . . . . . . . . . . 22
Four-Wheel Drive . . . . . . . . . . . . . . 23
Vehicle Features
Infotainment System . . . . . . . . . . . 24
Radio(s) . . . . . . . . . . . . . . . . . . . . . . . 24
Satellite Radio . . . . . . . . . . . . . . . . . 25
Portable Audio Devices . . . . . . . . 25
Bluetooth . . . . . . . . . . . . . . . . . . . . . . 25
Steering Wheel Controls . . . . . . . 26
Cruise Control . . . . . . . . . . . . . . . . . 26
Driver Information Center (DIC) . . . . . . . . . . . . . . . . . 27
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . . 27
Forward Automatic Braking (FAB) . . . . . . . . . . . . . . . . 27
Lane Departure Warning (LDW) . . . . . . . . . . . . . . . 28
Lane Keep Assist (LKA) . . . . . . . 28
Rear Vision Camera (RVC) . . . . 28
Parking Assist . . . . . . . . . . . . . . . . . 28
Power Outlets . . . . . . . . . . . . . . . . . 28
Universal Remote System . . . . . 29
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . 29
Performance and Maintenance
Traction Control/Electronic Stability Control . . . . . . . . . . . . . . 30
Tire Pressure Monitor . . . . . . . . . . 31
Fuel (Gasoline - Except L86 6.2L Engine) . . . . . . . . . . . . . 31 Fuel (Gasoline - L86 6.2L
Engine) . . . . . . . . . . . . . . . . . . . . . . . 32
Fuel (Diesel) . . . . . . . . . . . . . . . . . . . 32
E85 or FlexFuel . . . . . . . . . . . . . . . . 32
Engine Oil Life System . . . . . . . . 32
Driving for Better Fuel Economy . . . . . . . . . . . . . . . . . . . . . 33
Roadside Assistance Program . . . . . . . . . . . . . . . . . . . . . . 33

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
30 In Brief
To express-close the sunroof, fully
press and release
K. Press the
switch again to stop the movement.
Open/Close (Manual Mode) : To
open the sunroof, press and hold
I. Release the switch to stop the
movement. Press and hold
Kto
close the sunroof. Release the
switch to stop the movement.
Tilt Switch
Vent : From the closed position,
press
Jto vent the sunroof. Press
Kto close the vent. When the sunroof is opened, an air
deflector will automatically raise.
The air deflector will retract when
the sunroof is closed.
The sunroof also has a sunshade,
which can be pulled forward to block
sun rays. The sunshade must be
opened and closed manually.
If an object is in the path of the
sunroof while it is closing, the
automatic reversal system will
detect the object and stop the
sunroof.
See
Sunroof 055.
Performance and
Maintenance
Traction Control/
Electronic Stability
Control
The vehicle has a Traction Control
System (TCS) that limits wheel spin
and the StabiliTrak system that
assists with directional control of the
vehicle in difficult driving conditions.
Both systems come on
automatically when the vehicle is
started and begins to move.
.
To turn off TCS, press and
release
gon the center stack.
The traction off light
idisplays
in the instrument cluster. The
appropriate Driver Information
Center (DIC) message displays.
. To turn off both TCS and
StabiliTrak, press and hold
g
untiliandgilluminate in the
instrument cluster and the
appropriate DIC message
displays.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
In Brief 31
.Press and releasegagain to
turn on both systems.
StabiliTrak will automatically turn on
if the vehicle exceeds 56 km/h
(35 mph). Traction control will
remain off.
See Traction Control/Electronic
Stability Control 0282.
Tire Pressure Monitor
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The low tire pressure warning light
alerts to a significant loss in
pressure of one of the vehicle's
tires. If the warning light comes on,
stop as soon as possible and inflate
the tires to the recommended
pressure shown on the Tire and Loading Information label. See
Vehicle Load Limits
0248. The
warning light will remain on until the
tire pressure is corrected.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
may be an early indicator that the
tire pressures are getting low and
the tires need to be inflated to the
proper pressure.
The TPMS does not replace normal
monthly tire maintenance. Maintain
the correct tire pressures.
See Tire Pressure Monitor System
0 399.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure. See “Tire Fill Alert (If
Equipped)” underTire Pressure
Monitor Operation 0400.
Fuel (Gasoline - Except
L86 6.2L Engine)
Regular Fuel
Use only unleaded gasoline rated
87 octane or higher in your vehicle.
Do not use gasoline with an octane
rating lower as it may result in
vehicle damage and lower fuel
economy. See Fuel0299.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
In Brief 33
2. Fully press the acceleratorpedal slowly three times within
five seconds.
3. If the display changes to 100%, the system is reset.
See Engine Oil Life System 0353.
Driving for Better Fuel
Economy
Driving habits can affect fuel
mileage. Here are some driving tips
to get the best fuel economy
possible.
.
Avoid fast starts and accelerate
smoothly.
. Brake gradually and avoid
abrupt stops.
. Avoid idling the engine for long
periods of time.
. When road and weather
conditions are appropriate, use
cruise control.
. Always follow posted speed
limits or drive more slowly when
conditions require. .
Keep vehicle tires properly
inflated.
. Combine several trips into a
single trip.
. Replace the vehicle's tires with
the same TPC Spec number
molded into the tire's sidewall
near the size.
. Follow recommended scheduled
maintenance.
Roadside Assistance
Program
U.S.: 1-888-881-3302
TTY Users (U.S. Only):
1-888-889-2438
Canada: 1-800-268-6800
New GMC owners are automatically
enrolled in the Roadside Assistance
Program.
See Roadside Assistance Program
0 469.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
76 Seats and Restraints
Make sure the seat belt reminder
light is working. SeeSeat Belt
Reminders 0146.
Keep seat belts clean and dry. See
Seat Belt Care 076.
Seat Belt Care
Keep belts clean and dry.
{Warning
Do not bleach or dye seat belt
webbing. It may severely weaken
the webbing. In a crash, they
might not be able to provide
adequate protection. Clean and
rinse seat belt webbing only with
mild soap and lukewarm water.
Allow the webbing to dry.
Seat belts should be properly cared
for and maintained.
Seat belt hardware should be kept
dry and free of dust or debris. As
necessary exterior hard surfaces
and seat belt webbing may be lightly cleaned with mild soap and water.
Ensure there is not excessive dust
or debris in the mechanism. If dust
or debris exists in the system please
see the dealer. Parts may need to
be replaced to ensure proper
functionality of the system.
Replacing Seat Belt
System Parts after a
Crash
{Warning
A crash can damage the seat belt
system in the vehicle. A damaged
seat belt system may not properly
protect the person using it,
resulting in serious injury or even
death in a crash. To help make
sure the seat belt systems are
working properly after a crash,
have them inspected and any
necessary replacements made as
soon as possible.
After a minor crash, replacement of
seat belts may not be necessary.
But the seat belt assemblies that
were used during any crash may
have been stressed or damaged.
See your dealer to have the seat
belt assemblies inspected or
replaced.
New parts and repairs may be
necessary even if the seat belt
system was not being used at the
time of the crash.
Have the seat belt pretensioners
checked if the vehicle has been in a
crash, or if the airbag readiness light
stays on after you start the vehicle
or while you are driving. See
Airbag
Readiness Light 0147.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
78 Seats and Restraints
Warning (Continued)
seriously injured or killed. Do not
sit unnecessarily close to any
airbag, as you would be if sitting
on the edge of the seat or leaning
forward. Seat belts help keep you
in position before and during a
crash. Always wear a seat belt,
even with airbags. The driver
should sit as far back as possible
while still maintaining control of
the vehicle. The seat belts and
the front outboard passenger
airbags are most effective when
you are sitting well back and
upright in the seat with both feet
on the floor.
Occupants should not lean on or
sleep against the door or side
windows in seating positions with
seat-mounted side impact airbags
and/or roof-rail airbags.
{Warning
Children who are up against,
or very close to, any airbag when
it inflates can be seriously injured
or killed. Always secure children
properly in the vehicle. To read
how, seeOlder Children 092 or
Infants and Young Children 094.
There is an airbag readiness light
on the instrument cluster, which
shows the airbag symbol.
The system checks the airbag
electrical system for malfunctions.
The light tells you if there is an
electrical problem. See Airbag
Readiness Light 0147 for more
information.
Where Are the Airbags?
The driver frontal airbag is in the
center of the steering wheel.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Seats and Restraints 89
If the Off Indicator Is Lit for an
Adult-Sized Occupant
If a person of adult size is sitting in
the front outboard passenger seat,
but the off indicator is lit, it could be
because that person is not sitting
properly in the seat or that the child
restraint locking feature is engaged.
Use the following steps to allow the
system to detect that person and
enable the front outboard passenger
frontal airbag:1. Turn the vehicle off. 2. Remove any additional material
from the seat, such as
blankets, cushions, seat
covers, seat heaters, or seat
massagers.
3. Place the seatback in the fully upright position.
4. Have the person sit upright in the seat, centered on the seat
cushion, with legs comfortably
extended.
5. If the shoulder portion of the belt is pulled out all the way,
the child restraint locking
feature will be engaged. This
may unintentionally cause the
passenger sensing system to
turn the airbag off for some
adult-sized occupants. If this
happens, unbuckle the belt, let
the belt go back all the way,
and then buckle the belt again
without pulling the belt out all
the way.
6. Restart the vehicle and have the person remain in this
position for two to three minutes
after the on indicator is lit.
{Warning
If the front outboard passenger
airbag is turned off for an
adult-sized occupant, the airbag
will not be able to inflate and help
protect that person in a crash,
resulting in an increased risk of
serious injury or even death. An
adult-sized occupant should not
ride in the front outboard
passenger seat, if the passenger
airbag off indicator is lit.
Additional Factors Affecting
System Operation
Seat belts help keep the passenger
in position on the seat during
vehicle maneuvers and braking,
which helps the passenger sensing
system maintain the passenger
airbag status. See “Seat Belts”and
“Child Restraints” in the Index for
additional information about the
importance of proper restraint use.