
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
260 Driving and Operating
.Pressing the accelerator more
than one-quarter of the
way down.
. Turning the ignition off.
Retained Accessory
Power (RAP)
The following vehicle accessories
can be used for up to 10 minutes
after the engine is turned off:
.Audio System
. Power Windows
. OnStar System (if equipped)
. Sunroof (if equipped)
These features work when the key
is in ON/RUN or ACC/
ACCESSORY. Once the key is
turned from ON/RUN to LOCK/OFF,
the windows and sunroof continue
to work up to 10 minutes or until any
door is opened. The radio continues
to work for up to 10 minutes or until
the driver door is opened. Accessory Power Outlets (APOs)
The vehicle may have Accessory
Power Outlets (APOs) in several
locations. See
Power Outlets0133.
The APOs in the console or center
seat position are powered by
Retained Accessory Power (RAP).
They will continue to work for up to
10 minutes after the key is turned
from ON/RUN to LOCK/OFF, or until
the driver door is opened.
The APOs on the center stack come
from the factory powered directly
from the vehicle battery, and supply
accessory power at all times,
regardless of ignition key position.
If electronic items are left plugged
into these APOs for long periods of
time with the vehicle off, the vehicle
battery could be drained. The
vehicle may not start if the battery is
allowed to drain for an extended
period of time.
Engine Coolant Heater
The engine heater can provide
easier starting and better fuel
economy during engine warm-up in
cold weather conditions at or below
−18 °C (0 °F). Vehicles with an
engine heater should be plugged in
at least four hours before starting.
An internal thermostat in the
plug-end of the cord may exist,
which will prevent engine coolant
heater operation at temperatures
above −18 °C (0 °F).
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
{Warning
Do not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Vehicle Care 343
California Proposition
65 Warning
{Warning
Most motor vehicles, including
this one, as well as many of its
service parts and fluids, contain
and/or emit chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Engine
exhaust, many parts and
systems, many fluids, and some
component wear by-products
contain and/or emit these
chemicals. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0369
and Jump Starting - North America
0 426 and the back cover.
California Perchlorate
Materials Requirements
Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
Remote Keyless Entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications
Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty. Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see
Adding Equipment to the
Airbag-Equipped Vehicle 090.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
432 Vehicle Care
Warning (Continued)
be injured. Set the parking brake
before shifting the transfer case
to N (Neutral).
To dinghy tow: 1. Position the vehicle being towed behind the tow vehicle,
facing forward and on a level
surface.
2. Securely attach the vehicle being towed to the tow vehicle.
3. Apply the parking brake and start the engine.
4. Shift the transfer case to N (Neutral). See “Shifting into
N (Neutral)” underFour-Wheel
Drive 0272. Check that the
vehicle is in N (Neutral) by
shifting the transmission to
R (Reverse) and then to D
(Drive). There should be no
movement of the vehicle while
shifting.
5. Turn the engine off.
Caution
Failure to disconnect the negative
battery cable or to have it contact
the terminals can cause damage
to the vehicle.
6. Disconnect the negative battery cable at the battery and
secure the nut and bolt. Cover
the negative battery post with a
non-conductive material to
prevent any contact with the
negative battery terminal.
7. Shift the transmission to P (Park).
Caution
If the steering column is locked,
vehicle damage may occur.
8. Move the steering wheel to make sure the steering column
is unlocked. 9. With a foot on the brake pedal,
release the parking brake.
Keep the ignition key in the
towed vehicle in ACC/
ACCESSORY to prevent the
steering column from locking.
Disconnecting the Towed Vehicle
Before disconnecting the towed
vehicle: 1. Park on a level surface.
2. Set the parking brake, then shift the transmission to
P (Park), and turn the ignition
key off.
3. Connect the battery.
4. Apply the brake pedal.
5. Turn the ignition on with the engine off. Shift the transfer
case out of N (Neutral) to
Two-Wheel Drive High. See
“Shifting out of N (Neutral)”
under Four-Wheel Drive 0272.
See your dealer if the transfer
case cannot be shifted out of
N (Neutral).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
480 OnStar
Press=to:
. Open the OnStar app on the
infotainment display. See the
infotainment manual for
information on how to use the
OnStar app.
Or
. Make a call, end a call,
or answer an incoming call.
. Give OnStar Hands-Free Calling
voice commands.
. Give OnStar Turn-by-Turn
Navigation voice commands.
. Obtain and customize the Wi-Fi
hotspot name or SSID and
password, if equipped.
Press
Qto connect to an
Advisor to:
. Verify account information or
update contact information. .
Get driving directions.
. Receive a Diagnostic check of
the vehicle's key operating
systems.
. Receive Roadside Assistance.
. Manage Wi-Fi Settings,
if equipped.
Press
>to get a priority connection
to an OnStar Advisor available
24/7 to:
. Get help for an emergency.
. Be a Good Samaritan or
respond to an AMBER Alert.
. Get assistance in severe
weather or other crisis situations
and find evacuation routes.
OnStar Services
Emergency
Emergency Services require an
active, OnStar service plan
(excludes Basic Plan). With
Automatic Crash Response, built-in
sensors can automatically alert a
specially trained OnStar Advisor
who is immediately connected in to
the vehicle to help.
Press
>for a priority connection to
an OnStar Advisor who can contact
emergency service providers, direct
them to your exact location, and
relay important information.
With OnStar Crisis Assist, specially
trained Advisors are available
24 hours a day, 7 days a week, to
provide a central point of contact,
assistance, and information during a
crisis.
With Roadside Assistance, Advisors
can locate a nearby service provider
to help with a flat tire, a battery
jump, or an empty gas tank.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
484 OnStar
3. Say the entire number withoutpausing, including a “1”and the
area code. System responds:
“OK, calling.”
Calling 911 Emergency
1. Press=. System responds:
“OnStar ready.”
2. Say “Call.”System responds:
“Call. Please say the name or
number to call.”
3. Say “911”without pausing.
System responds: “911.”
4. Say “Call.”System responds:
“OK, dialing 911.”
Retrieve My Number
1. Press=. System responds:
“OnStar ready.”
2. Say “My number.” System
responds: “Your OnStar
Hands-Free Calling number is,”
then says the number.
End a Call
Press=. System responds: “Call
ended.”
Verify Minutes and Expiration
Press=and say “Minutes” then
“Verify” to check how many minutes
remain and their expiration date.
Diagnostics
By monitoring and reporting on the
vehicle’s key systems, OnStar
Advanced Diagnostics provides a
way to keep up on maintenance.
Capabilities vary by model. See
www.onstar.com for details and
system limitations. Message and
data rates may apply.
Includes:
. Diagnostic Alerts: Set
preferences to receive real-time
e-mails, texts, or monthly
reports of the vehicle’s health.
Or press
Qto have an Advisor
initiate a remote diagnostic
report. .
Proactive Alerts: Receive a
real-time e-mail or text message
regarding potential issues with
key vehicle components, such
as the battery, fuel system,
or starter system. Alerts for
potential issues appear on the
infotainment display. Proactive
Alerts are designed to help
predict specific types of issues
based on information collected
from the vehicle. Other factors
may affect vehicle performance.
Not all issues will deliver alerts.
In some cases, a dealer service
check may be required to
confirm the accuracy of the
alerts.
. Dealer Maintenance Notification:
Have the vehicle notify your
preferred dealer when it is time
for maintenance. Your dealer will
then contact you to set up an
appointment.
To begin, pressQto speak to an
Advisor, or see www.onstar.com.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Index 499
Parking (cont'd)Over Things That Burn . . . . . . . 264
Parking Assist . . . . . . . . . . . . . . . . . . 289
Parking or Backing Assistance Systems . . . . . . . . . . 289
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . . . . . . 149
Passenger Compartment Air Filter . . . . . . . . . . . . . . . . . . . . . . . . . . 232
Passenger Sensing System . . . . . 86
Perchlorate Materials Requirements, California . . . . . . 343
Personalization Vehicle . . . . . . . . . . . . . . . . . . . . . . . 165
Phone Apple CarPlay andAndroid Auto . . . . . . . . . . . . . . . . 217
Bluetooth . . . . . . . . . . . . . . . . 211, 213
Pickup Conversion to Chassis Cab . . . . . . . . . . . . . . . . . . 340
Port USB . . . . . . . . . . . . . . . . . . . . . . . . . . 197
Power
Door Locks . . . . . . . . . . . . . . . . . . . . . 41
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Outlets . . . . . . . . . . . . . . . . . . . . . . . 133
Protection, Battery . . . . . . . . . . . . 185
Retained Accessory (RAP) . . . 260 Power (cont'd)
Seat Adjustment . . . . . . . . . . . . . . . . 60
Steering Fluid . . . . . . . . . . . . . . . . . 365
Windows . . . . . . . . . . . . . . . . . . . . . . . 52
Power Assist Steps . . . . . . . . . . . . . . 43
Pregnancy, Using Seat Belts . . . . 74
Privacy Vehicle Data Recording . . . . . . . 477
Program
Courtesy Transportation . . . . . . 471
Proposition 65 Warning,
California . . . . . . . . . . . .343, 369, 426, Back Cover
R
Radio Frequency Statement . . . . 475
Radio Reception . . . . . . . . . . . . . . . . 193
Radios
AM-FM Radio . . . . . . . . . . . . . . . . . 190
Satellite . . . . . . . . . . . . . . . . . . . . . . . 192
Reading Lamps . . . . . . . . . . . . . . . . . 183
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . 371 Locking . . . . . . . . . . . . . . . . . . . . . . . 285
Rear Seats . . . . . . . . . . . . . . . . . . 66, 68
Rear Vision Camera (RVC) . . . . . 289
Rear Windows . . . . . . . . . . . . . . . . . . . 54
Rearview Mirrors . . . . . . . . . . . . . . . . 52 Rearview Mirrors (cont'd)
Automatic Dimming . . . . . . . . . . . . . 52
Reclining Seatbacks . . . . . . . . . . . . . 61
Recognition Voice . . . . . . . . . . . . . . . . . . . . . . . . . 205
Recommended Fluids and Lubricants . . . . . . . . . . . . . . . . . . . . . 456
Records Maintenance . . . . . . . . . . . . . . . . . . 459
Recreational Vehicle Towing . . . . 430
Reimbursement Program, GM Mobility . . . . . . . . . . . . . . . . . . . 469
Remote Keyless Entry (RKE) System . . . . . . . . . . . . . . . . . . . . . . . . . 37
Remote Vehicle Start . . . . . . . . . . . . 39
Replacement Parts Airbags . . . . . . . . . . . . . . . . . . . . . . . . . 92
Maintenance . . . . . . . . . . . . . . . . . . 458
Replacing Airbag System . . . . . . . . 92
Replacing LATCH System Parts after a Crash . . . . . . . . . . . . 111
Replacing Seat Belt System Parts after a Crash . . . . . . . . . . . . . 76
Reporting Safety Defects Canadian Government . . . . . . . . 476
General Motors . . . . . . . . . . . . . . . 477
U.S. Government . . . . . . . . . . . . . 476