23 MPG combined isn’t going to win any green awards, but for the 2018 Mercedes-Benz AMG C43 4matic, it’s simply part of the deal. This isn’t a car bought by someone prioritizing fuel sipping; it’s a precision instrument designed for rapid point-to-point driving, wrapped in a cloak of understated luxury. The C43 buyer wants performance first, and the twin-turbo V6 delivers that strongly. They accept the fuel economy as a necessary trade-off for the exhilarating experience.

City and highway performance

The EPA estimates the C43 4matic at 20 MPG in the city and 27 MPG on the highway. Stop-and-go driving will naturally drag down the overall figure, but the 9-speed automatic transmission makes the most of the engine’s broad torque band. On the open road, cruising at a steady speed, achieving the EPA highway number should be readily attainable. The 4MATIC all-wheel-drive system adds a bit of weight and complexity, but its performance benefits in all weather conditions outweigh the slight fuel economy penalty for many buyers.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2018 Mercedes-Benz AMG C43 4matic at $2,500. This figure is based on driving 15,000 miles per year and using the national average fuel price. Of course, your actual fuel costs will vary depending on your driving habits, the type of fuel you use, and local fuel prices. It’s a useful benchmark, however, for comparing the C43’s running costs to other vehicles. Remember that premium fuel is recommended for optimal performance, so you’ll want to factor that into your budget.

Real-world expectations

While the EPA provides a standardized benchmark, real-world fuel economy often differs. C43 owners who enjoy the car’s performance capabilities will likely see figures closer to the low 20s in mixed driving. A more conservative driver, with predominantly highway miles, might be able to consistently achieve the EPA’s combined rating, or even slightly better. But spirited driving, especially in sport and sport+ modes, will quickly send the MPG plummeting.

How it compares

Compared to its rivals, the C43’s fuel economy falls within a reasonable range for the performance it offers. The BMW M340i xDrive, a direct competitor, achieves around 25 MPG combined. The Audi S4, another strong contender, mirrors the C43’s combined rating at 23 MPG. The Lexus IS 350 F Sport, typically chosen for its reliability rather than outright performance, manages around 22 MPG combined. For potential buyers, this means the C43’s fuel consumption is not a significant outlier within its competitive set. They are willing to pay more at the pump for the overall AMG experience, but that does not mean that other options do not have better combined MPG.

Looking at AMG MPG across all years can give an idea about the fuel economy across their range of vehicles.

Tips to maximize efficiency

Anticipate traffic flow and avoid unnecessary acceleration. The C43’s responsive engine can tempt lead-footedness, but gentle acceleration and maintaining a consistent speed will significantly improve fuel economy. The 9-speed transmission will automatically select the most efficient gear, but your throttle input greatly influences shift patterns.

Make use of the “Comfort” drive mode for everyday driving. This mode softens throttle response, optimizes shift points for efficiency, and improves fuel consumption compared to the sportier settings. Avoid constantly driving in “Sport” or “Sport+” mode, as these prioritize performance over efficiency.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, which reduces fuel economy. Check your tire pressure regularly and maintain the recommended pressure listed on the door jamb placard. Every little bit helps, and properly inflated tires also improve handling and tire wear.

Minimize idling. Modern engines are designed to be efficient when running, even at low speeds. Excessive idling burns fuel without covering any distance. If you’re stopped for more than a minute, consider turning off the engine. This advice is good across all Mercedes Benz fuel economy data and all makes and models.

Reduce aerodynamic drag. While the C43 is designed for performance, you can still minimize drag by removing unnecessary items from the roof rack or cargo carrier when not in use. These items increase air resistance and reduce fuel efficiency, especially at higher speeds.