The 20 MPG combined delivered by the 2020 GMC Sierra 2WD with the 2.7L turbocharged four-cylinder engine isn’t going to set any records, but it’s a perfectly acceptable figure for a full-size truck aimed at a specific type of buyer. This Sierra configuration is for a customer who needs the utility of a pickup but isn’t regularly towing heavy loads or hauling construction materials. They want a truck that can handle weekend projects, occasional trips to the lumber yard, and maybe pulling a small boat, all while keeping fuel costs reasonable. They prioritize a comfortable ride and modern technology over maximum payload capacity.

City and highway performance

The EPA estimates the 2020 GMC Sierra 2WD 2.7L at 19 MPG in the city and 22 MPG on the highway. These numbers reflect the engine’s tuning and the eight-speed automatic transmission’s ability to keep the engine in its most efficient range. The city MPG is respectable considering the truck’s size and weight, suggesting the turbocharger provides ample low-end torque to get moving without excessive throttle input.

The highway MPG, while decent, indicates that aerodynamic drag becomes a more significant factor at higher speeds, as is typical for vehicles with a pickup truck profile. The relatively small engine works harder at highway speeds, especially when headwinds are present. This highlights why a driver who anticipates mostly highway driving might consider stepping up to the larger V8, sometimes, paradoxically, more displacement can lead to similar, or even slightly improved, MPG in specific use cases.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2020 GMC Sierra 2WD 2.7L at exactly $2,200. This figure is based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway. It also assumes the prevailing national average fuel price at the time of calculation. Naturally, your individual fuel costs will vary depending on how many miles you drive annually and where you live because local fuel prices fluctuate. It’s a useful benchmark, though, for comparing this particular Sierra’s running costs against those of other pickups or even SUVs that might be under consideration. You can use resources to find all Gmc fuel economy data compared to other trucks.

Real-world expectations

While the EPA estimates provide a standardized baseline, real-world fuel economy often differs based on driving habits, traffic conditions, and terrain. Drivers with a heavy foot or those frequently operating in stop-and-go traffic will likely see numbers below the EPA estimates. Conversely, those who practice smooth acceleration, maintain consistent speeds, and avoid unnecessary idling may be able to achieve fuel economy closer to, or even slightly exceeding, the EPA figures. Towing or carrying heavy loads will also have a significant negative impact on fuel economy, as the engine will be working harder to maintain speed. Careful trip planning and anticipating traffic flow can contribute to better results.

How it compares

The fuel economy of the 2020 GMC Sierra 2WD 2.7L stacks up differently depending on the competition. For example, a comparable Ford F-150 with its 2.7L EcoBoost V6 is rated at 20 MPG combined and 20 MPG highway, mirroring the Sierra. A Ram 1500 with the eTorque 3.6L V6 achieves 22 MPG highway, claiming a slight edge. However, those gains often come with added complexity (and potential maintenance) from the hybrid assist systems. The Chevrolet Silverado, essentially the same truck as the Sierra, offers identical fuel economy numbers with its 2.7L turbo. These comparisons matter because buyers in this segment often cross-shop between the Big Three truck brands, and even a 1-2 MPG difference can sway a purchasing decision when projected over the life of the vehicle. Review SIERRA MPG across all years compared to these popular trucks.

Tips to maximize efficiency

One of the easiest ways to improve fuel economy in the 2020 GMC Sierra 2WD 2.7L is to consciously modify your driving style. Avoid aggressive acceleration and hard braking. The Sierra’s eight-speed transmission is designed to shift smoothly and keep the engine in its optimal power band, so let it do its job without constantly demanding maximum power.

Proper tire inflation is also critical. Check your tires regularly to ensure they are inflated to the recommended pressure listed on the door jamb label. Underinflated tires increase rolling resistance, which forces the engine to work harder and consume more fuel. Using the correct tire pressure also improves handling and extends tire life.

Reduce unnecessary weight in the truck bed. Hauling around extra tools, equipment, or other items adds to the vehicle’s overall weight and reduces fuel economy. Only carry what you need for the current trip. Even removing a tonneau cover can help marginally, as these add weight but also marginally improve aerodynamics.

Minimize idling. Excessive idling consumes fuel without covering any distance. If you anticipate being stationary for more than a minute, turn off the engine. Modern vehicles, including the Sierra, are designed to handle frequent starts and stops without causing significant wear and tear.

Plan your trips efficiently. Combine multiple errands into a single trip to minimize cold starts. A warm engine operates more efficiently than a cold one. Mapping out the most direct route can also help you avoid unnecessary miles and reduce fuel consumption.