2021 GMC Sierra
36 configurations — EPA fuel economy ratings
| Trim / Variant | City MPG | Hwy MPG | Combined MPG | Fuel | Drive | Engine | Transmission |
|---|---|---|---|---|---|---|---|
| Sierra 2WD | 15 | 21 | 17 | Regular Gasoline | Rear-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra 2WD | 15 | 19 | 16 | Regular Gasoline | Rear-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra 2WD | 17 | 23 | 19 | Regular Gasoline | Rear-Wheel Drive | 5.3L 8-cyl | Automatic 8-spd |
| Sierra 2WD | 23 | 30 | 26 | Diesel | Rear-Wheel Drive | 3L 6-cyl Turbo | Automatic 10-spd |
| Sierra 2WD | 16 | 21 | 17 | Regular Gasoline | Rear-Wheel Drive | 4.3L 6-cyl | Automatic 6-spd |
| Sierra 2WD | 20 | 23 | 21 | Regular Gasoline | Rear-Wheel Drive | 2.7L 4-cyl Turbo | Automatic 8-spd |
| Sierra 2WD | 20 | 23 | 21 | Regular Gasoline | Rear-Wheel Drive | 2.7L 4-cyl Turbo | Automatic 8-spd |
| Sierra 2WD | 14 | 21 | 16 | Regular Gasoline | Rear-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra 2WD | 15 | 22 | 17 | Regular Gasoline | Rear-Wheel Drive | 5.3L 8-cyl | Automatic 8-spd |
| Sierra 4WD | 15 | 20 | 16 | Premium Gasoline | 4-Wheel Drive | 6.2L 8-cyl | Automatic 10-spd |
| Sierra 4WD | 22 | 26 | 24 | Diesel | 4-Wheel Drive | 3L 6-cyl Turbo | Automatic 10-spd |
| Sierra 4WD | 18 | 21 | 19 | Regular Gasoline | 4-Wheel Drive | 2.7L 4-cyl Turbo | Automatic 8-spd |
| Sierra 4WD | 14 | 20 | 16 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 8-spd |
| Sierra 4WD | 14 | 20 | 16 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra 4WD | 18 | 20 | 19 | Regular Gasoline | 4-Wheel Drive | 2.7L 4-cyl Turbo | Automatic 8-spd |
| Sierra 4WD | 16 | 20 | 17 | Premium Gasoline | 4-Wheel Drive | 6.2L 8-cyl | Automatic 10-spd |
| Sierra 4WD | 16 | 22 | 19 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 10-spd |
| Sierra 4WD | 15 | 20 | 17 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra 4WD | 16 | 21 | 18 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 8-spd |
| Sierra 4WD | 14 | 18 | 16 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra 4WD | 15 | 20 | 17 | Regular Gasoline | 4-Wheel Drive | 4.3L 6-cyl | Automatic 6-spd |
| Sierra 4WD | 15 | 21 | 18 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 10-spd |
| Sierra 4WD AT4 | 15 | 21 | 17 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 10-spd |
| Sierra 4WD AT4 | 15 | 19 | 17 | Premium Gasoline | 4-Wheel Drive | 6.2L 8-cyl | Automatic 10-spd |
| Sierra 4WD AT4 | 22 | 26 | 24 | Diesel | 4-Wheel Drive | 3L 6-cyl Turbo | Automatic 10-spd |
| Sierra 4WD AT4 | 16 | 21 | 18 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 10-spd |
| Sierra 4WD AT4 | 16 | 21 | 18 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 8-spd |
| Sierra 4WD AT4 | 14 | 18 | 16 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra 4WD AT4 | 14 | 20 | 16 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 8-spd |
| Sierra 4WD AT4 | 14 | 19 | 16 | Premium Gasoline | 4-Wheel Drive | 6.2L 8-cyl | Automatic 10-spd |
| Sierra Cab Chassis 2WD | 13 | 18 | 14 | Regular Gasoline | Rear-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra Cab Chassis 2WD | 15 | 19 | 17 | Regular Gasoline | Rear-Wheel Drive | 4.3L 6-cyl | Automatic 6-spd |
| Sierra Cab Chassis 2WD | 14 | 18 | 15 | Regular Gasoline | Rear-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra Cab Chassis 4WD | 14 | 17 | 15 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra Cab Chassis 4WD | 13 | 17 | 14 | Regular Gasoline | 4-Wheel Drive | 5.3L 8-cyl | Automatic 6-spd |
| Sierra Cab Chassis 4WD | 14 | 16 | 15 | Regular Gasoline | 4-Wheel Drive | 4.3L 6-cyl | Automatic 6-spd |