wheel alignment GMC SIERRA 2021 Owner's Manual

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Instruments and Controls 135
Ride Height
Touch and the following may display:
.Automatic Entry/Egress
Automatic Entry/Egress
This feature specifies if the vehicle will
automatically lower to make it easier to
enter or exit the vehicle.
Touch Off or On.
Running Boards
Touch and the following may display:
.Automatic Running Boards
.Deploy Running Boards
Automatic Running Boards
This feature specifies the position and use of
the running boards.
Touch Off or On.
Deploy Running Boards
This feature moves the running boards to a
deployed position so they can be used with
the doors closed.
Touch Off or Deploy.
Seating Position
Touch and the following may display:
.Seat Entry Memory
.Seat Exit Memory
Seat Entry Memory
This feature automatically recalls the
previously stored 1 or 2 button positions
when the ignition is changed from off to on
or ACC/ACCESSORY. See Memory Seats049.
Touch Off or On.
Seat Exit Memory
This feature automatically recalls the
previously stored exit button position when
the ignition is changed from on or ACC/
ACCESSORY to off and the driver door is
open. See Memory Seats 049.
Touch Off or On.
Suspension
Touch and the following may display:
.Service Mode
.Alignment Mode Service Mode
This feature disables the air suspension
system and is used to prevent unintended
raising or lowering of the suspension.
Touch Off or On.
Alignment Mode
This feature will optimize the vehicle height
to provide the most accurate wheel
alignment.
Touch Off or On.
Trailering
Touch and the following may display:
.Side Trailer Camera
.Bed View Camera Lighting
Side Trailer Camera
This feature specifies if using the turn signal
during a lane change will also display an
applicable side view of the trailer and
vehicle. See Assistance Systems for Parking
or Backing 0266.
Touch Off or On.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Vehicle Care 321
Vehicle Care
General Information
General Information . . . . . . . . . . . . . . . . . . . 322
California Proposition 65 Warning . . . . . 322
California Perchlorate MaterialsRequirements . . . . . . . . . . . . . . . . . . . . . . . . 322
Accessories and Modifications . . . . . . . . . 323
Vehicle Checks
Doing Your Own Service Work . . . . . . . . . 323
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Engine Compartment Overview . . . . . . . . 325
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 330
Engine Oil Life System . . . . . . . . . . . . . . . . . 332
Automatic Transmission Fluid . . . . . . . . . . 333
Engine Air Filter Life System . . . . . . . . . . . 333
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . 334
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 335
Engine Overheating . . . . . . . . . . . . . . . . . . . 338
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . 340
Engine Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 341
Brake Pad Life System . . . . . . . . . . . . . . . . . 342
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 343
Battery - North America . . . . . . . . . . . . . . . 343 Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 346
Front Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 346
Starter Switch Check . . . . . . . . . . . . . . . . . . 347
Automatic Transmission Shift Lock
Control Function Check . . . . . . . . . . . . . . 347
Ignition Transmission Lock Check . . . . . . 347
Park Brake and P (Park) Mechanism Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 347
Wiper Blade Replacement . . . . . . . . . . . . . 348
Glass Replacement . . . . . . . . . . . . . . . . . . . . 348
Windshield Replacement . . . . . . . . . . . . . . 348
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . 350
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . . . . . . . . . . 350
Halogen Bulbs . . . . . . . . . . . . . . . . . . . . . . . . . 350
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
Headlamps, Front Turn Signal, Sidemarker, and Parking Lamps . . . . . . 350
Taillamps, Turn Signal, Stoplamps, and Back-Up Lamps . . . . . . . . . . . . . . . . . . . . . . . 351
Center High-Mounted Stoplamp (CHMSL) and Cargo Lamp . . . . . . . . . . . . 352
License Plate Lamp . . . . . . . . . . . . . . . . . . . . 352
Electrical System
Electrical System Overload . . . . . . . . . . . . . 352
Fuses and Circuit Breakers . . . . . . . . . . . . . 353
Engine Compartment Fuse Block . . . . . . . 353
Instrument Panel Fuse Block (Left) . . . . . 357
Instrument Panel Fuse Block (Right) . . . 358
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . 361
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . 362
Tire Sidewall Labeling . . . . . . . . . . . . . . . . . 362
Tire Designations . . . . . . . . . . . . . . . . . . . . . . 364
Tire Terminology and Definitions . . . . . . 365
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Tire Pressure Monitor System . . . . . . . . . 368
Tire Pressure Monitor Operation . . . . . . 369
Tire Inspection . . . . . . . . . . . . . . . . . . . . . . . . . 373
Tire Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . 374
When It Is Time for New Tires . . . . . . . . 375
Buying New Tires . . . . . . . . . . . . . . . . . . . . . 376
Different Size Tires and Wheels . . . . . . . . 377
Uniform Tire Quality Grading . . . . . . . . . . 377
Wheel Alignment and Tire Balance . . . . 378
Wheel Replacement . . . . . . . . . . . . . . . . . . . 378
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 380
Tire Changing . . . . . . . . . . . . . . . . . . . . . . . . . . 381
Full-Size Spare Tire . . . . . . . . . . . . . . . . . . . . 390

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
374 Vehicle Care
Replace the tire if:
.The indicators at three or more
places around the tire can be seen.
.There is cord or fabric showing
through the tire's rubber.
.The tread or sidewall is cracked, cut,
or snagged deep enough to show
cord or fabric.
.The tire has a bump, bulge, or split.
.The tire has a puncture, cut, or other
damage that cannot be repaired well
because of the size or location of the
damage.
Tire Rotation
Tires should be rotated every 12 000 km
(7,500 mi). SeeMaintenance Schedule
0 409.
Tires are rotated to achieve a more
uniform wear for all tires. The first
rotation is the most important.
Anytime unusual wear is noticed, rotate
the tires as soon as possible, check for
proper tire inflation pressure, and check
for damaged tires or wheels. If the unusual wear continues after the
rotation, check the wheel alignment.
See
When It Is Time for New Tires 0375
and
Wheel Replacement 0378.Use this rotation pattern when rotating
the tires.
Do not include the spare tire in the tire
rotation.
Adjust the front and rear tires to the
recommended inflation pressure on the
Tire and Loading Information label after the tires have been rotated. See
Tire
Pressure 0367 and
Vehicle Load Limits 0222.
Reset the Tire Pressure Monitor System.
See Tire Pressure Monitor Operation
0 369.
Check that all wheel nuts are properly
tightened. See “Wheel Nut Torque”
under Capacities and Specifications
0 424.
{Warning
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
cause wheel nuts to become loose
over time. The wheel could come off
and cause a crash. When changing a
wheel, remove any rust or dirt from
places where the wheel attaches to
the vehicle. In an emergency, a cloth
or paper towel can be used; however,
use a scraper or wire brush later to
remove all rust or dirt.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
378 Vehicle Care
times as well on the government course
as a tire graded 100. The relative
performance of tires depends upon the
actual conditions of their use, however,
and may depart significantly from the
norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.
Traction
The traction grades, from highest to
lowest, are AA, A, B, and C. Those
grades represent the tire's ability to
stop on wet pavement as measured
under controlled conditions on specified
government test surfaces of asphalt and
concrete. A tire marked C may have
poor traction performance. Warning:
The traction grade assigned to this tire
is based on straight-ahead braking
traction tests, and does not include
acceleration, cornering, hydroplaning,
or peak traction characteristics.Temperature
The temperature grades are A (the
highest), B, and C, representing the
tire's resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled conditions
on a specified indoor laboratory test
wheel. Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to
sudden tire failure. The grade C
corresponds to a level of performance
which all passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B and A
represent higher levels of performance
on the laboratory test wheel than the
minimum required by law. Warning:
The temperature grade for this tire is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, underinflation, or excessive
loading, either separately or in
combination, can cause heat buildup
and possible tire failure.Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider an
alignment check if there is unusual tire wear
or the vehicle is significantly pulling to one
side or the other. Some slight pull to the
left or right, depending on the crown of the
road and/or other road surface variations
such as troughs or ruts, is normal. If the
vehicle is vibrating when driving on a
smooth road, the tires and wheels may
need to be rebalanced. See your dealer for
proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked,
or badly rusted or corroded. If wheel nuts
keep coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If the
wheel leaks air, replace it. Some aluminum
wheels can be repaired. See your dealer if
any of these conditions exist.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
Service and Maintenance 417
Vehicle Care
To help keep the vehicle looking like new,
vehicle care products are available from your
dealer. For information on how to clean and
protect the vehicle’s interior and exterior,
seeInterior Care 0403 and
Exterior Care 0398.
Wheel Alignment
Wheel alignment is critical for ensuring that
the tires deliver optimal wear and
performance.
.Signs that the alignment may need to be
adjusted include pulling, improper vehicle
handling, or unusual tire wear.
.Your dealer has the required equipment
to ensure proper wheel alignment.
Windshield
For safety, appearance, and the best
viewing, keep the windshield clean and
clear.
.Signs of damage include scratches, cracks,
and chips.
.Trained dealer technicians can inspect the
windshield and recommend proper
replacement if needed. Wiper Blades
Wiper blades need to be cleaned and kept in
good condition to provide a clear view.
.Signs of wear include streaking, skipping
across the windshield, and worn or split
rubber.
.Trained dealer technicians can check the
wiper blades and replace them when
needed.

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-14632426) - 2021 - CRC - 11/5/20
458 Index
Storage Compartments . . . . . . . . . . . . . . . . . . . 95
StrutsGas . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Stuck Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 221
Sun Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Sunroof . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Symbols . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
System Brake Pad Life . . . . . . . . . . . . . . . . . . . . . . . . . 342
Engine Air Filter Life . . . . . . . . . . . . . . . . . . . 333
Forward Collision Alert (FCA) . . . . . . . . . . . 275
Global Positioning . . . . . . . . . . . . . . . . . . . . . . 173
Infotainment . . . . . . . . . . . . . . . . . . . . . . . . . . . 439
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 173
Systems
Driver Assistance . . . . . . . . . . . . . . . . . . . . . . 265
T
Tachometer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .110
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
TaillampsBulb Replacement . . . . . . . . . . . . . . . . . . . . . . 351
Task Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Teen Driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192
Text Telephone (TTY) Users . . . . . . . . . . . . . . 430
Theft-Deterrent Systems . . . . . . . . . . . . . . . . . . .32 Immobilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 360
All-Season . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
All-Terrain . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 362
Buying New Tires . . . . . . . . . . . . . . . . . . . . . . 376
Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
Changing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 381
Designations . . . . . . . . . . . . . . . . . . . . . . . . . . . 364
Different Size . . . . . . . . . . . . . . . . . . . . . . . . . . 377
Full-Size Spare . . . . . . . . . . . . . . . . . . . . . . . . . 390
If a Tire Goes Flat . . . . . . . . . . . . . . . . . . . . . 380
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373
Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Pressure Light . . . . . . . . . . . . . . . . . . . . . . . . . 122
Pressure Monitor Operation . . . . . . . . . . . 369
Pressure Monitor System . . . . . . . . . . . . . . 368
Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 374
Sidewall Labeling . . . . . . . . . . . . . . . . . . . . . . 362
Terminology and Definitions . . . . . . . . . . . 365
Uniform Tire Quality Grading . . . . . . . . . . 377
Wheel Alignment and Tire Balance . . . . 378
Wheel Replacement . . . . . . . . . . . . . . . . . . . . 378
When It Is Time for New Tires . . . . . . . . . 375
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
Tow/Haul Mode . . . . . . . . . . . . . . . . . . . . . . . . . 242
Tow/Haul Mode Light . . . . . . . . . . . . . . . . . . . . 119 Towing
Driving Characteristics . . . . . . . . . . . . . . . . . 288
Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 296
General Information . . . . . . . . . . . . . . . . . . . 288
Recreational Vehicle . . . . . . . . . . . . . . . . . . . 395
Trailer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293
Trailer Sway Control (TSC) . . . . . . . . . . . . . 306
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
Traction Limited-Slip Differential . . . . . . . . . . . . . . . . 254
Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Traction Control/Electronic Stability Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Trademarks and License Agreements . . . . . 195
Trailer Sway Control (TSC) . . . . . . . . . . . . . . . . . . . . 306
Tow Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 293
Trailer Towing App . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Trailering App . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Transfer Case . . . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Transmission
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Fluid, Automatic . . . . . . . . . . . . . . . . . . . . . . . 333
Transportation Program, Courtesy . . . . . . . 433
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . . . . . .110
Truck-Camper Loading Information . . . . . . . 226

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-14632426) - 2021 - CRC - 11/5/20
Index 459
Turn and Lane-Change Signals . . . . . . . . . . . .143
Turn SignalBulb Replacement . . . . . . . . . . . . . . . . . . . . . . 351
U
Underseat Storage . . . . . . . . . . . . . . . . . . . . . . . . 96
Uniform Tire Quality Grading . . . . . . . . . . . . 377
Universal Remote System . . . . . . . . . . . . . . . . 136Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138
Programming . . . . . . . . . . . . . . . . . . . . . . . . . . 136
Updates Map Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
USB Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .158
Using the Navigation System . . . . . . . . . . . . 163
Using the System . . . . . . . . . . . . . . . . . . . . . . . . . 152
Using This Manual . . . . . . . . . . . . . . . . . . . . . . . . . .2
V
Vehicle Alarm System . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Canadian Owners . . . . . . . . . . . . . . . . . . . . . . . . 2
Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Identification Number (VIN) . . . . . . . . . . . . 423
Load Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Personalization . . . . . . . . . . . . . . . . . . . . . . . . . 131
Remote Start . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Vehicle (cont'd)
Speed Messages . . . . . . . . . . . . . . . . . . . . . . . . 131
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 394
Vehicle Ahead Indicator . . . . . . . . . . . . . . . . . . . 119
Vehicle Care Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . 367
Vehicle Data Recording and Privacy . . . . . . 437
Vehicle Positioning . . . . . . . . . . . . . . . . . . . . . . .174
Vehicle Security
Steering Column Lock . . . . . . . . . . . . . . . . . . . 32
Ventilation, Air . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Voice Recognition . . . . . . . . . . . . . . . . . . . . . . . . . 175
Voltmeter Gauge . . . . . . . . . . . . . . . . . . . . . . . . . 113
W
Warning Brake System Light . . . . . . . . . . . . . . . . . . . . . 117
Caution and Danger . . . . . . . . . . . . . . . . . . . . . 2
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106
Warnings
Hazard Flashers . . . . . . . . . . . . . . . . . . . . . . . . 142
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Wheels Alignment and Tire Balance . . . . . . . . . . . . 378
Different Size . . . . . . . . . . . . . . . . . . . . . . . . . . 377
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 378 When It Is Time for New Tires . . . . . . . . . . . 375
Where to Put the Restraint . . . . . . . . . . . . . . . 76
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Rear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
Windshield
Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . 348
Wiper/Washer . . . . . . . . . . . . . . . . . . . . . . . . . 101
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 220
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 361
Wiper Blade Replacement . . . . . . . . . . . . . . . . 348
Wireless Charging . . . . . . . . . . . . . . . . . . . . . . . 103