2021 GMC Sierra
The EPA lists 35 versions of the 2021 GMC Sierra. Combined fuel economy ranges from 14 to 26 MPG; the most efficient version is rated 23 city / 30 highway.
At a glance
- Fuel economy
- 14 to 26 MPG combined
Sources: NHTSA complaints, recalls and 5-Star ratings; U.S. EPA
Fuel economy
The EPA lists 35 versions of the 2021 GMC Sierra. Combined fuel economy ranges from 14 to 26 MPG; the most efficient version is rated 23 city / 30 highway.