17 MPG combined is the price to join owners of the 2021 Mercedes-Benz AMG GT C Roadster. Few people shopping for this open-top performance machine prioritize fuel economy. They’re buying a hand-built V8 sound, a statement of personal style, and a visceral driving experience that few cars can match. The fuel consumption is simply a footnote on the window sticker, a gentle reminder that thrilling performance comes at a cost.

City and highway performance

The EPA estimates the AMG GT C Roadster will achieve 15 MPG in the city and 20 MPG on the highway. The large difference between city and highway figures reflects the nature of this car. In urban environments, stop-and-go traffic forces the engine to constantly accelerate and decelerate, negating any potential fuel savings. And the temptation to unleash the V8’s power is ever-present. On the open road, at a steady cruise, the engine operates more efficiently, but even then, the AMG GT C Roadster isn’t designed for maximizing fuel economy. The aerodynamic profile, while stunning, is optimized for high-speed stability, not low drag. Gear selection of the AM7 (automatic 7-speed) transmission will make a difference.

Annual fuel cost

The EPA estimates an annual fuel cost of $3,400 for the 2021 Mercedes-Benz AMG GT C Roadster. This assumes 15,000 miles of driving per year, with approximately 55% city driving and 45% highway driving, and using the national average fuel price for premium gasoline. It’s a substantial figure, but it’s unlikely to deter the target demographic. Owners of cars in this price bracket are generally less sensitive to fuel costs, particularly when balanced against the pleasure derived from driving a car like this. In other words, the pleasure from driving the AMG GT C Roadster offsets the discomfort from seeing how much you pay at the pump.

Real-world expectations

The EPA figures provide a useful baseline, but real-world fuel economy can vary considerably depending on driving style, traffic conditions, and even the type of gasoline used. Drivers who regularly exploit the AMG GT C Roadster’s performance potential will likely see lower fuel economy figures than the EPA estimates. Conversely, those who drive predominantly on the highway and adopt a more conservative driving style might achieve numbers closer to, or even slightly above, the EPA highway rating. Tire pressure also plays a minor role.

Keep in mind that consistent hard acceleration and heavy braking will decimate fuel mileage in any performance car, especially this one.

How it compares

The Porsche 911 Turbo S Cabriolet, another high-performance convertible, achieves a slightly better 17 MPG city / 23 MPG highway rating. The Audi R8 V10 Spyder, while boasting a naturally aspirated V10 engine, posts similar numbers to the AMG at 13 city / 20 highway. These comparisons are less about finding a “fuel-efficient” option and more about understanding the relative efficiency within this niche segment. If fuel economy is a serious concern, this segment of high-performance luxury vehicles is simply not the right arena. To see all Mercedes Benz fuel economy data, explore our website.

Tips to maximize efficiency

While the AMG GT C Roadster isn’t inherently fuel-efficient, there are a few steps a driver can take to improve its mileage. Anticipate traffic flow and avoid unnecessary acceleration and braking. Smooth, consistent driving will minimize fuel consumption compared to an aggressive, stop-start style. Take advantage of the different drive modes. Selecting “Comfort” mode will generally result in better fuel economy than “Sport+” as the engine and transmission are programmed for less aggressive performance.

Ensure the tires are properly inflated. Under-inflated tires increase rolling resistance, which reduces fuel economy. Refer to the sticker on the driver’s side doorjamb for the recommended tire pressure. Premium gasoline is required for optimal performance in the AMG GT C Roadster. Using lower-octane fuel can reduce performance and potentially damage the engine, negating any potential cost savings. The AMG badge stands for “Aufrecht Melcher Großaspach” and for high performance; the trade off is lower efficiency.

Avoid idling for extended periods. If you know you’ll be stopped for more than a minute, it’s generally more fuel-efficient to turn off the engine. Idling consumes fuel without providing any benefit. Lighten the load. Removing unnecessary weight from the car can slightly improve fuel economy. Every little bit helps, even in a car like the AMG GT C Roadster.

Finally, keep up with scheduled maintenance. A properly maintained engine runs more efficiently. Regular oil changes, air filter replacements, and spark plug inspections can all contribute to better fuel economy. For a specific view of AMG MPG across all years, our data is accessible.