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GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada/Mexico-14632286) - 2021 - CRC - 11/19/20
Contents
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Keys, Doors, and Windows . . . . . . . . . . . . . . . 7
Seats and Restraints . . . . . . . . . . . . . . . . . . . . 46
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 96
Instruments and Controls . . . . . . . . . . . . . . 100
Lighting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
Infotainment System . . . . . . . . . . . . . . . . . . . 149
Climate Controls . . . . . . . . . . . . . . . . . . . . . . . 205
Driving and Operating . . . . . . . . . . . . . . . . . . 212
Vehicle Care . . . . . . . . . . . . . . . . . . . . . . . . . . . . 307
Service and Maintenance . . . . . . . . . . . . . . . 389
Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . 403
Customer Information . . . . . . . . . . . . . . . . . . 407
Reporting Safety Defects . . . . . . . . . . . . . . . 415
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 419
Connected Services . . . . . . . . . . . . . . . . . . . . . 424
Index. . . . . . . . . . . . . . . . . . . . . . . . . . 427
Introduction
The names, logos, emblems, slogans, vehicle
model names, and vehicle body designs
appearing in this manual including, but not
limited to, GM, the GM logo, GMC, the GMC
Truck Emblem, SIERRA, and DENALI are
trademarks and/or service marks of General
Motors LLC, its subsidiaries, affiliates,
or licensors.
For vehicles first sold in Canada, substitute
the name
“
General Motors of Canada
for GMC Division wherever it
This manual describes features that may or
may not be on the vehicle because of
optional equipment that was not purchased
on the vehicle, model variants, country
specifications, features/applications that may
not be available in your region, or changes
subsequent to the printing of this owner
manual.
If the vehicle has the Duramax diesel
engine, see the Duramax diesel supplement
for additional and specific information on
this engine.
Refer to the purchase documentation
relating to your specific vehicle to confirm
the features.
Keep this manual in the vehicle for quick
reference.
Litho in U.S.A.
Part No. 84744494 B Second Printing
©
2020 General Motors LLC. All Rights Reserved.