An 18 MPG combined rating for the 2020 Mercedes-Benz AMG GT Roadster 4.0L 8-cyl isn’t a selling point, but it also isn’t a surprise. Nobody shopping for a twin-turbocharged V8 roadster expects Prius-level efficiency. Instead, the fuel economy is simply the cost to enter a world of blistering acceleration and open-top thrills. This car exists for those who prioritize performance and exclusivity above all else.

City and highway performance

The AMG GT Roadster’s EPA ratings break down to 16 MPG in the city and 22 MPG on the highway. The thirsty figures are a direct result of the hand-built 4.0-liter V8 engine producing 550 horsepower (in standard GT trim; the GT C offers more). The engine’s responsiveness, combined with the AMG Speedshift DCT 7-speed transmission, encourages frequent and aggressive use of the throttle, which in turn impacts fuel consumption. While 22 MPG sounds reasonable for highway cruising, maintaining that number requires a disciplined right foot and minimal use of the car’s passing power. You won’t always be able to resist, of course, and the payoff is worth it.

Annual fuel cost

The EPA estimates that the annual fuel cost for the 2020 Mercedes-Benz AMG GT Roadster is $3,200. This figure is based on driving 15,000 miles per year and using the national average fuel price for premium gasoline, which is required for optimal performance in this engine. Those who drive more aggressively, or exceed 15,000 miles annually, can expect to spend considerably more. For many AMG GT Roadster owners, this $3,200 is a small price to pay for the driving experience the car delivers. It’s a rounding error compared to the price of the vehicle itself.

Real-world expectations

While the EPA provides a standardized benchmark, real-world fuel economy for the AMG GT Roadster varies significantly based on driving style and conditions. Owners who spend more time in stop-and-go traffic will likely see numbers closer to the 16 MPG city rating, or even lower. A weekend road trip with a focus on enjoying the car’s performance will also result in lower MPG, especially if you’re pushing the car hard on winding roads. Conversely, consistent highway driving at moderate speeds can potentially yield results slightly better than the EPA’s 22 MPG estimate. But let’s be honest: few AMG GT Roadster drivers prioritize squeezing every last mile out of a gallon.

How it compares

Fuel economy isn’t typically high on the list of considerations for buyers in this segment, but it’s still useful to see how the AMG GT Roadster compares to its rivals. The Porsche 911 Carrera S Cabriolet, for example, achieves 20 MPG combined with its turbocharged inline-6 engine. The Jaguar F-Type R Convertible with its supercharged V8 manages a similar 18 MPG combined, mirroring the AMG GT. Aston Martin’s Vantage Roadster, another key competitor, comes in around 18 MPG combined as well with its AMG-sourced V8. These numbers underscore that the AMG GT Roadster’s fuel consumption is typical for high-performance roadsters, with small variations attributable to engine design and weight. Explore all Mercedes Benz fuel economy data for a broader perspective.

Tips to maximize efficiency

While the AMG GT Roadster isn’t known for its frugality, there are ways to optimize fuel consumption without sacrificing too much enjoyment. The AMG Dynamic Select system offers various driving modes, including a “Comfort” mode that prioritizes efficiency by softening throttle response and optimizing gear selection. While not ideal for unleashing the car’s full potential, it’s suitable for daily commuting and highway cruising when maximum fuel savings are desired.

Gentle acceleration and smooth braking techniques make a noticeable difference. The AMG GT Roadster’s instant torque delivery is seductive, but resisting the urge to constantly floor the accelerator can significantly improve fuel economy. Anticipate traffic flow and avoid abrupt stops to minimize energy waste. Regular maintenance, including proper tire inflation and timely oil changes, also plays an important role in maximizing efficiency. A well-maintained engine runs more smoothly and efficiently, leading to improved MPG.

Consider the route you’re taking. Avoiding stop-and-go traffic and congested areas helps to minimize fuel consumption. Opting for routes with consistent speeds and fewer intersections can make a difference, especially during peak hours. Explore AMG MPG across all years for more information on AMG fuel efficiency.

Use cruise control on the highway to maintain a consistent speed and minimize fluctuations in fuel consumption. Consistent speeds reduce the need for frequent acceleration and deceleration, which can significantly impact fuel economy over long distances. However, be mindful of traffic conditions and adjust speed accordingly for safety.