2021 GMC SIERRA ABS

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-14632426) - 2021 - CRC - 11/5/20
398 Vehicle Care
Caution
Do not tow this vehicle with two wheels
on the ground, or vehicle damage could
occur. This damage would not be covered
by the vehicle warranty.
Dolly towing this vehicle is not allowed with
either the front or the rear tires on the
ground for two-wheel drive or four-wheel
drive, regardless of transfer case.
Appearance Care
Exterior Care
Locks
Locks are lubricated at the factory. Use a
de-icing agent only when absolutely
necessary, and have the locks greased after
using. See Recommended Fluids and
Lubricants 0418.
Washing the Vehicle
To preserve the vehicle's finish, wash it
often and out of direct sunlight.
{Warning
Do not power wash any part of the
vehicle’s interior, including the vinyl floor
covering. This could damage safety and
other systems in the vehicle, which
would not be covered by the vehicle
warranty.
Caution
Do not use petroleum-based, acidic,
or abrasive cleaning agents as they can
damage the vehicle's paint, metal,
or plastic parts. If damage occurs, it
would not be covered by the vehicle
warranty. Approved cleaning products can
be obtained from your dealer. Follow all
manufacturer directions regarding correct
product usage, necessary safety
precautions, and appropriate disposal of
any vehicle care product.
Caution
Avoid using high-pressure washes closer
than 30 cm (12 in) to the surface of the
vehicle. Use of power washers exceeding
8 274 kPa (1,200 psi) can result in
damage or removal of paint and decals.
Cleaning Underhood Components
Caution
Do not power wash any component
under the hood that has this
e
symbol.
This could cause damage that would not
be covered by the vehicle warranty.
Solvents or aggressive cleaners may harm
underhood components. The usages of these
chemicals should be avoided.
Recommend water only.
A pressure washer may be used, but care
must be utilized. The following criteria must
be followed:
.Water pressure must be kept below
14 000 KPa (2,000 PSI).
.Water temperature must be below 80 °C
(180 °F).

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-14632426) - 2021 - CRC - 11/5/20
448 Index
IndexA
Accessories and Modifications . . . . . . . . . . . 323
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . 236
Active Fuel Management . . . . . . . . . . . . . . . . 237
Adaptive Cruise Control . . . . . . . . . . . . . . . . . . 256
Add-On Electrical Equipment . . . . . . . . . . . . . .318
Adding a Snow Plow or SimilarEquipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .318
Additional Information OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 441
Additional Maintenance and Care . . . . . . . . .415
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . . . . . . 48
Agreements
Trademarks and License . . . . . . . . . . . . . . . 195
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . 334
Air Conditioning . . . . . . . . . . . . . . . . . . . . 204, 206
Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 333
Air Filter, Passenger Compartment . . . . . . . 209
Air Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 209
Airbag System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 70
How Does an Airbag Restrain? . . . . . . . . . . 64
Passenger Sensing System . . . . . . . . . . . . . . 66
What Makes an Airbag Inflate? . . . . . . . . . 64
What Will You See after an AirbagInflates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65 Airbag System (cont'd)
When Should an Airbag Inflate? . . . . . . . . 63
Where Are the Airbags? . . . . . . . . . . . . . . . . 62
Airbags Adding Equipment to the Vehicle . . . . . . . 69
Passenger Status Indicator . . . . . . . . . . . . . . 114
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . . 114
Servicing Airbag-Equipped Vehicles . . . . . . 69
System Check . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Alarm Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . . 31
Alert
Lane Change . . . . . . . . . . . . . . . . . . . . . . . . . . . 280
Side Blind Zone (SBZA) . . . . . . . . . . . . . . . . . 280
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 361
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 362
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 155
Antenna Fixed Mast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Multi-band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158
Antilock Brake System (ABS) . . . . . . . . . . . . . 246
Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 398
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 403
Apple CarPlay and Android Auto . . . . . . . . . .185

GMC Sierra/Sierra Denali 1500 Owner Manual (GMNA-Localizing-U.S./Cana-
da/Mexico-14632426) - 2021 - CRC - 11/5/20
454 Index
LED Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
LightingEntry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Exit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Illumination Control . . . . . . . . . . . . . . . . . . . 145
LED . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 350
Task . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144
Lights Airbag Readiness . . . . . . . . . . . . . . . . . . . . . . . 114
Antilock Brake System (ABS)Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 118
Brake System Warning . . . . . . . . . . . . . . . . . 117
Charging System . . . . . . . . . . . . . . . . . . . . . . . 115
Check Engine (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . 123
Door Ajar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Driver Mode Control . . . . . . . . . . . . . . . . . . . . 121
Electric Parking Brake . . . . . . . . . . . . . . . . . . . 117
Electronic Stability Control (ESC), Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Engine Coolant Temperature Warning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 121
Engine Oil Pressure . . . . . . . . . . . . . . . . . . . . 122
Flash-to-Pass . . . . . . . . . . . . . . . . . . . . . . . . . . . . 141
Four-Wheel-Drive . . . . . . . . . . . . . . . . . . . . . . . 118
Front Fog Lamp . . . . . . . . . . . . . . . . . . . . . . . . 123
High-Beam On . . . . . . . . . . . . . . . . . . . . . . . . . 123 Lights (cont'd)
High/Low Beam Changer . . . . . . . . . . . . . . . 141
Hill Descent Control . . . . . . . . . . . . . . . . . . . . 119
Lane Keep Assist . . . . . . . . . . . . . . . . . . . . . . . . 119
Low Fuel Warning . . . . . . . . . . . . . . . . . . . . . 122
Seat Belt Reminders . . . . . . . . . . . . . . . . . . . . 113
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Service Electric Parking Brake . . . . . . . . . . . 118
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Tow/Haul Mode . . . . . . . . . . . . . . . . . . . . . . . . 119
Traction Off . . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Limited-Slip Differential . . . . . . . . . . . . . . . . . . 254
Lock
Steering Column . . . . . . . . . . . . . . . . . . . . . . . . 32
Locking Rear Axle . . . . . . . . . . . . . . . . . . . . . . . . 254
Locks Automatic Door . . . . . . . . . . . . . . . . . . . . . . . . . 22
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . 22
Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Lockout Protection . . . . . . . . . . . . . . . . . . . . . . 22
Power Door . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . . . . 215
Low Fuel Warning Light . . . . . . . . . . . . . . . . . . 122
Lower Anchors and Tethers for Children (LATCH System) . . . . . . . . . . . . . . . . .77
Lumbar Adjustment . . . . . . . . . . . . . . . . . . . . . . . 48 Front Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48M
MaintenanceRecords . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Maintenance and Care Additional . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 415
Maintenance Schedule . . . . . . . . . . . . . . . . . . . 409 Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
Transfer Case . . . . . . . . . . . . . . . . . . . . . . . . . . 242
Malfunction Indicator Lamp . . . . . . . . . . . . . . . 115
Manual Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . .241
Manual Windows . . . . . . . . . . . . . . . . . . . . . . . . . .41
Map Data Updates . . . . . . . . . . . . . . . . . . . . . . . . 175
Maps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Media
Avoiding Untrusted Devices . . . . . . . . . . . . 158
Memory Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
Messages Engine Power . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 130
Vehicle Speed . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Mirror Rear Camera . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Mirrors Automatic Dimming . . . . . . . . . . . . . . . . . . . . 37
Automatic Dimming Rearview . . . . . . . . . . 38
Blind Spot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37