
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
440 Vehicle Care
Steering, Suspension, and
Chassis Components
Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of wear at
least once a year.
Inspect power steering for proper
attachment, connections, binding,
leaks, cracks, chafing, etc.
Visually check constant velocity joint
boots and axle seals for leaks.
1500 Series vehicles, at least every
other oil change lubricate the outer
tie rod ends.
2500/3500 Series vehicles, at least
every other engine oil change
lubricate the upper and lower
control arm ball joints. Control arm
ball joints on 1500 series vehicles
are maintenance-free.
2500/3500 Series vehicles equipped
with steering linkage, at least every
other engine oil change lubricate the
tie rod ball joints, idler arm pivot
shaft bearings, idler arm socket, and
pitman arm socket.
Caution
Lubrication of applicable steering/
suspension points should not be
done unless the temperature is
−12 °C (10 °F) or higher,
or damage could result.
For an eAssist vehicle, see the
Silverado/Sierra eAssist
supplement.
Body Component Lubrication
Lubricate all key lock cylinders,
hood hinges, liftgate hinges, and the
steel fuel door hinge unless the
components are plastic. Applying
silicone grease on weatherstrips
with a clean cloth will make them
last longer, seal better, and not stick
or squeak.
Underbody Maintenance
At least twice a year, spring and fall,
use plain water to flush any
corrosive materials from the
underbody. Take care to thoroughly
clean any areas where mud and other debris can collect. If equipped
with power assist steps, extend
them and then use a high pressure
wash to clean all joints and gaps.
Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water
can overcome the seals and
contaminate the fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and
should be replaced.
Sheet Metal Damage
If the vehicle is damaged and
requires sheet metal repair or
replacement, make sure the body
repair shop applies anti-corrosion
material to parts repaired or
replaced to restore corrosion
protection.
Original manufacturer replacement
parts will provide the corrosion
protection while maintaining the
vehicle warranty.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Service and Maintenance 449
.Check tire inflation pressures.
See Tire Pressure 0397.
. Inspect tire wear. See Tire
Inspection 0404.
. Visually check for fluid leaks.
. Inspect engine air cleaner filter.
See Engine Air Cleaner/Filter
0 358.
. Inspect brake system. See
Exterior Care 0435.
. Visually inspect steering,
suspension, and chassis
components for damaged, loose,
or missing parts or signs of wear
at least once a year. See
Exterior Care 0435. Lubricate
the suspension and steering
components at least every other
oil change. (If equipped with
grease fittings)
. Check restraint system
components. See Safety System
Check 075. .
Visually inspect fuel system for
damage or leaks.
. Visually inspect exhaust system
and nearby heat shields for
loose or damaged parts.
. Lubricate body components. See
Exterior Care 0435.
. Check starter switch. See Starter
Switch Check 0374.
. Check automatic transmission
shift lock control function. See
Automatic Transmission Shift
Lock Control Function Check
0374.
. Check ignition transmission lock.
See Ignition Transmission Lock
Check 0374.
. Check parking brake and
automatic transmission park
mechanism. See Park Brake and
P (Park) Mechanism Check
0 375. .
Check accelerator pedal for
damage, high effort, or binding.
Replace if needed.
. Visually inspect gas strut for
signs of wear, cracks, or other
damage. Check the hold open
ability of the strut. If the hold
open ability is low, service the
gas strut. See Gas Strut(s)
0 376.
. Inspect sunroof track and seal,
if equipped. See Sunroof055.
. Verify spare tire key lock
operation and lubricate as
needed. See Tire Changing
0 415.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Service and Maintenance 457
UsageFluid/Lubricant
Front Axle –Four-Wheel Drive SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 88900401, in
Canada 89021678).
Hydraulic Brake System DOT 3 Hydraulic Brake Fluid (GM Part No. 19353126, in Canada 19299819).
Hydraulic Power Steering System (2500/3500 Series Only) GM Power Steering Fluid (GM Part No. 19329450, in Canada 19329451).
Key Lock Cylinders, Hood Hinges, Body Door Hinge Pins, Tailgate
Hinge and Linkage, Fuel Door Hinge,
Tailgate Handle Pivot Points, Hinges, Latch Bolt, and Linkage Multi-Purpose Lubricant, Superlube (GM Part No. 12346241, in
Canada 10953474).
Rear Axle (1500 Series) SAE 75W-85 Synthetic Axle Lubricant (GM Part No. 19300457, in Canada 19300458).
Rear Axle (2500/3500 Series) SAE 75W-90 Synthetic Axle Lubricant (GM Part No. 88900401, in Canada 89021678).
Transfer Case (Four-Wheel Drive) DEXRON-VI Automatic Transmission Fluid.
Weatherstrip Conditioning Weatherstrip Lubricant (GM Part No. 3634770, in Canada 10953518) or Dielectric Silicone Grease (GM Part No. 12345579, in Canada 10953481).
Weatherstrip Squeaks Synthetic Grease with Teflon, Superlube (GM Part No. 12371287, in Canada 10953437).
Windshield Washer Automotive windshield washer fluid that meets regional freeze protection requirements.

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
496 Index
General Information (cont'd)Vehicle Care . . . . . . . . . . . . . . . . . . 342
Glove Box . . . . . . . . . . . . . . . . . . . . . . 124
GM Mobility Reimbursement Program . . . . . . . . . . . . . . . . . . . . . . . 469
H
Halogen Bulbs . . . . . . . . . . . . . . . . . . 378
Hazard Warning Flashers . . . . . . . 180
Head Restraints . . . . . . . . . . . . . . . . . 58
HeadlampsAiming . . . . . . . . . . . . . . . . . . . . . . . . 377
Automatic . . . . . . . . . . . . . . . . . . . . . 179
Bulb Replacement . . . . . . . . . . . . 378
Daytime RunningLamps (DRL) . . . . . . . . . . . . . . . . 179
Flash-to-Pass . . . . . . . . . . . . . . . . . 179
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . 378
High-Beam On Light . . . . . . . . . . 157
High/Low Beam Changer . . . . . 179
Lamps On Reminder . . . . . . . . . 157
Heated Steering Wheel . . . . . . . . . . . . . . . 130
Heated and Ventilated Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . . 65
Heated Mirrors . . . . . . . . . . . . . . . . . . . 50 Heater
Engine Coolant . . . . . . . . . . . . . . . 260
Heating . . . . . . . . . . . . . . .224, 226, 228
High Voltage Devices and Wiring . . . . . . . . . . . . . . . . . . . . . . . . . 380
High-Beam On Light . . . . . . . . . . . . 157
High-Speed Operation . . . . . . . . . . 399
Hill and Mountain Roads . . . . . . . . 245
Hill Descent Control (HDC) . . . . . 284
Hill Descent Control Light . . . . . . . 153
Hill Start Assist (HSA) . . . . . . . . . . 282
Home Page . . . . . . . . . . . . . . . . . . . . . 189
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . 344
Horn . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
How to Wear Seat Belts Properly . . . . . . . . . . . . . . . . . . . . . . . . 70
HVAC . . . . . . . . . . . . . . . . .224, 226, 228
I
Idle System Fast . . . . . . . . . . . . . . . . . . . . . . . . . . 259
Ignition Positions . . . . . . . . . . . . . . . 256
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . . . 374
Immobilizer . . . . . . . . . . . . . . . . . . . . . . 46
Indicator Vehicle Ahead . . . . . . . . . . . . . . . . 154 Infants and Young Children,
Restraints . . . . . . . . . . . . . . . . . . . . . . 94
Infotainment . . . . . . . . . . . . . . . . . . . . 186
Infotainment System . . . . . . . . . . . . 478
Instrument Cluster . . . . . . . . . . . . . . 138
Instrument Panel Storage Area . . . . . . . . . . . . . . . . . 124
Interior Rearview Mirrors . . . . . . . . . 51
Introduction . . . . . . . . . . . . . . . . . . . . . . . 2
J
Jack Auxiliary . . . . . . . . . . . . . . . . . . . . . . 203
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . 426
K
Keyless EntryRemote (RKE) System . . . . . . . . . 37
Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
L
Labeling, Tire Sidewall . . . . . . . . . . 391
Lamps Auxiliary RoofMounted Lamp . . . . . . . . . . . . . . 182
Cargo . . . . . . . . . . . . . . . . . . . . . . . . . 183
Daytime Running (DRL) . . . . . . 179
Dome . . . . . . . . . . . . . . . . . . . . . . . . . 183

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