21 MPG combined is respectable for the 2019 GMC Sierra C10 2WD with the 2.7L turbocharged four-cylinder engine. It’s important to consider who buys this Sierra. It’s not usually for heavy hauling across the country. It’s often a fleet vehicle, a regional contractor’s workhorse, or for homeowners needing occasional light-duty capability who prioritize daily drivability and relatively lower running costs. For such buyers, 21 MPG balances utility with frugality.

City and highway performance

The EPA estimates the Sierra 2.7L achieves 20 MPG in the city and 23 MPG on the highway. The city number is important. Many full-size trucks get mileage in the mid-teens around town, making the Sierra’s mileage a real advantage for those in urban environments, whether job sites or running errands. The 23 MPG highway rating is still commendable, especially compared to V8-powered trucks. The eight-speed automatic transmission helps by keeping the engine in its most efficient range at cruising speeds.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2019 GMC Sierra C10 2WD 2.7L is $2,100. This is based on driving 15,000 miles per year and using national average fuel prices. While individual spending varies based on driving and local fuel costs, this $2,100 provides a benchmark for comparing the Sierra against competitors. A driver who drives significantly more each year, or lives where gas prices are higher, can expect higher expenses. As of current writing, the annual cost is expected to be significantly higher because of rising national average fuel prices.

Real-world expectations

EPA estimates are useful for comparison, but real-world fuel economy varies. Several factors influence what you see on the road. Driving style is critical, aggressive acceleration and hard braking reduce fuel efficiency. Load weight also plays a role, the more you haul, the lower your MPG. Environmental conditions, such as wind resistance and weather, affect mileage. Expect slightly lower figures than the EPA estimates if you routinely tow, drive aggressively, or live with stop-and-go traffic. Conversely, careful drivers who commute on the highway may see better results.

How it compares

The 2019 Sierra 2.7L’s fuel economy situation is unique. The Ford F-150 with its 2.7L EcoBoost V6 consistently delivers slightly better figures, with EPA estimates around 22 MPG combined. The Ram 1500 with the eTorque V6 gets numbers in a similar range. The Sierra excels against V8-powered trucks. A comparable Sierra with the 5.3L V8 often struggles to reach 19 MPG combined. For buyers who don’t need the V8’s extra power and prioritize fuel efficiency, the 2.7L is attractive. Reviewing SIERRA MPG across all years can offer further insight. Buyers should also use all Gmc fuel economy data as a point of comparison.

Tips to maximize efficiency

One important way to improve fuel economy in the GMC Sierra 2.7L is to pay attention to tire pressure. Underinflated tires increase rolling resistance, forcing the engine to work harder and burning more fuel. Check your tire pressure regularly and inflate to the recommended levels on the door jamb sticker.

Avoid excessive idling. The 2.7L turbo engine consumes fuel when stationary. If you anticipate being stopped for more than a minute, turn off the engine. This simple habit can improve fuel economy, especially in city driving.

Use cruise control on the highway when possible. Maintaining a consistent speed reduces unnecessary acceleration and deceleration, leading to more consistent fuel consumption. The eight-speed transmission is optimized for highway cruising, so let it do its job.

Consider removing any unnecessary weight from the truck bed. The less weight the engine has to haul, the better your fuel economy. Removing tools or materials not needed for the trip can add up to savings.