Photo: GMC Sierra by Ethan Llamas, CC BY-SA 4.0, via Wikimedia Commons. It shows the model, not always this exact version.
GMC · model year 2021
2021 GMC Sierra Cab Chassis 4WD
Special purpose · 4-Wheel Drive · Gas · EPA class: Special Purpose Vehicle 4WD
EPA figures · 2021fueleconomy.gov
15MPG combined
14/16MPG city / highway
$4,450fuel a year
592 g CO₂ per mile 4.3 L 6-cyl Automatic 6-spd
This car on fueleconomy.gov, read 2 October 2026. Your own figures depend on how and where you drive.
Where it places
Every figure on record
- Combined MPG
- 15 MPG
- City MPG
- 14 MPG
- Highway MPG
- 16 MPG
- Annual fuel cost
- $4,450
- Tailpipe CO₂
- 592 g per mile
- Model year
- 2021
- Body
- Special purpose
- EPA size class
- Special Purpose Vehicle 4WD
- Drive
- 4-Wheel Drive
- Engine
- 4.3 L 6-cyl
- Transmission
- Automatic 6-spd
- Fuel
- Gasoline
Efficiency
Running cost
The car
Powertrain
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14 MPG · $4,800 fuel a year 2021 GMC Sierra Cab Chassis 4WD
15 MPG · $4,450 fuel a year 2021 GMC Sierra Cab Chassis 4WD
14 MPG · $4,800 fuel a year