2025 · Full-Size Pickup · Gas / Flex-fuel
2025 GMC Sierra MPG & fuel economy
The 2025 GMC Sierra is a full-size pickup offered in 16 EPA-rated configurations. The most efficient version returns 19 MPG combined (18 city / 21 highway) on regular gasoline. Across the lineup, combined ratings range from 15 to 19 MPG. That's down 1 MPG from the 2024 model. Among 22 full-size pickups rated for 2025, it ranks 20th for lowest fuel cost. At 15,000 miles a year with $3.10/gal regular gas, it costs about $2,447 a year to fuel.
What will it cost you?
Your mileage and prices are saved and used across the site.
Fuel average
The 2025 GMC Sierra's fuel average is 8.1 km/L (12.4 L/100 km), or 19 MPG combined: 7.7 km/L in the city and 8.9 km/L on the highway.
| MPG | km/L | L/100 km | |
|---|---|---|---|
| City | 18 | 7.7 | 13.1 |
| Highway | 21 | 8.9 | 11.2 |
| Combined | 19 | 8.1 | 12.4 |
How it ranks among 2025 Full-Size Pickups
Full class ranking →Annual fuel cost at 15,000 miles and default prices; shorter bars cost less.
Sierra MPG across model years
Full history →16 EPA-rated configurations
| Configuration | Type | City | Hwy | Combined | Range | Your cost / yr |
|---|---|---|---|---|---|---|
| RWD · 2.7L 4-cyl turbo · 8-speed automatic Sierra 2WD |
Gas | 18 MPG | 21 MPG | 19 MPG | — | $2,447 |
| RWD · 2.7L 4-cyl turbo · 8-speed automatic Sierra 2WD |
Gas | 17 MPG | 21 MPG | 19 MPG | — | $2,447 |
| RWD · 5.3L 8-cyl · 10-speed automatic Sierra 2WD |
Gas | 16 MPG | 21 MPG | 18 MPG | — | $2,583 |
| 4WD · 2.7L 4-cyl turbo · 8-speed automatic Sierra 4WD |
Gas | 17 MPG | 19 MPG | 18 MPG | — | $2,583 |
| RWD · 5.3L 8-cyl · 10-speed automatic Sierra 2WD |
Gas | 16 MPG | 20 MPG | 17 MPG | — | $2,735 |
| 4WD · 2.7L 4-cyl turbo · 8-speed automatic Sierra 4WD |
Gas | 17 MPG | 18 MPG | 17 MPG | — | $2,735 |
| 4WD · 5.3L 8-cyl · 10-speed automatic Sierra 4WD |
Flex-fuel | 15 MPG | 19 MPG | 17 MPG | — | $2,735 |
| 4WD · 5.3L 8-cyl · 10-speed automatic Sierra 4WD |
Gas | 15 MPG | 19 MPG | 17 MPG | — | $2,735 |
| 4WD · 2.7L 4-cyl turbo · 8-speed automatic Sierra Mud Terrain Tires 4WD |
Gas | 16 MPG | 17 MPG | 16 MPG | — | $2,906 |
| 4WD · 5.3L 8-cyl · 10-speed automatic Sierra 4WD |
Gas | 15 MPG | 19 MPG | 16 MPG | — | $2,906 |
| 4WD · 5.3L 8-cyl · 10-speed automatic Sierra Mud Terrain Tires 4WD |
Gas | 15 MPG | 18 MPG | 16 MPG | — | $2,906 |
| RWD · 5.3L 8-cyl · 10-speed automatic Sierra Cab Chassis 2WD |
Gas | 15 MPG | 18 MPG | 16 MPG | — | $2,906 |
| 4WD · 5.3L 8-cyl · 10-speed automatic Sierra Cab Chassis 4WD |
Gas | 14 MPG | 16 MPG | 15 MPG | — | $3,100 |
| 4WD · 6.2L 8-cyl · 10-speed automatic Sierra 4WD |
Gas | 15 MPG | 19 MPG | 16 MPG | — | $3,703 |
| 4WD · 6.2L 8-cyl · 10-speed automatic Sierra Mud Terrain Tires 4WD |
Gas | 14 MPG | 17 MPG | 15 MPG | — | $3,950 |
| 4WD · 6.2L 8-cyl · 10-speed automatic Sierra 4WD AT4X |
Gas | 14 MPG | 16 MPG | 15 MPG | — | $3,950 |
Specs (most efficient configuration)
- Fuel
- Regular gasoline
- Engine / motor
- 2.7L 4-cyl turbo
- Transmission
- 8-speed automatic
- Drivetrain
- RWD
- Tailpipe CO₂
- 468 g/mi
- EPA fuel economy score
- 4/10
- EPA greenhouse gas score
- 4/10
2025 GMC Sierra vs. rivals
Compare the 2025 Sierra
With any other car from any year, including other Sierra model years. Type a year to jump, e.g. "2015 Accord".
Same year, other powertrains: 2025 GMC Sierra Diesel (26 MPG), 2025 GMC Sierra EV (64 MPGe)
Frequently asked questions
What is the gas mileage of the 2025 GMC Sierra?
Up to 19 MPG combined (18 city / 21 highway); ratings range from 15 to 19 MPG depending on configuration.
What fuel does the 2025 GMC Sierra use?
Regular gasoline.
What is the fuel average in km/L for the 2025 GMC Sierra?
The 2025 GMC Sierra's fuel average is 8.1 km/L (12.4 L/100 km), or 19 MPG combined: 7.7 km/L in the city and 8.9 km/L on the highway.
How much does it cost to fuel the 2025 GMC Sierra per year?
About $2,447 at 15,000 miles a year with $3.10/gal regular gas, or $16.32 per 100 miles. Use the calculator on this page to plug in your own mileage and prices.