2015 Mercedes-Benz SLS AMG GT Roadster Fuel Economy

15 MPG combined is not a typo. The 2015 Mercedes-Benz SLS AMG GT Roadster, with its snarling 6.2L V8, exists in a realm where fuel efficiency is a distant afterthought, a sacrifice willingly made for a visceral driving experience. This isn’t transportation; it’s a statement, a thrill ride, a glorious anachronism. Buyers aren’t cross-shopping for the best gas mileage; they’re prioritizing the sound of a naturally aspirated V8 and the wind in their hair.

City and highway performance

The EPA estimates paint a clear picture: 13 MPG in the city and 19 MPG on the highway. The urban figure reflects the stop-and-go nature of city driving, coupled with the AMG’s tendency to encourage enthusiastic acceleration. The highway number, while better, still lags behind most modern performance cars, a result of the big engine’s thirst, even at cruising speeds. The automatic (AM7) transmission, while offering smooth and rapid shifts, does little to mitigate the inherent fuel consumption of a high-performance V8.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2015 Mercedes-Benz SLS AMG GT Roadster at $3,850. This calculation assumes 15,000 miles of driving per year, with a mix of city and highway miles, using the prevailing national average fuel price. For context, that’s roughly the cost of a decent used motorcycle, or many months worth of lease payments on a more economical vehicle. This figure underscores the cost of entry into the world of high-performance motoring, beyond the initial purchase price. For owners, this is simply the price of admission to the exclusive club of SLS ownership.

Real-world expectations

Real-world MPG will vary. Aggressive driving, frequent track days, and prolonged idling will push fuel economy below the EPA estimates. It is true that a more restrained driving style, with a focus on maintaining consistent speeds on the highway, might yield slightly better results; however, few SLS AMG GT Roadster owners are likely to prioritize hypermiling techniques. The car begs to be driven hard. Driving on a track and some canyon carving is almost guaranteed to drop MPG figures significantly.

How it compares

Compared to other high-performance GT cars of its era, the SLS AMG GT Roadster’s fuel economy is predictably low. A contemporary Porsche 911 Turbo S Cabriolet, for example, achieves around 19 MPG combined, a significant improvement. Even the Aston Martin V12 Vantage Roadster, with its larger engine, manages around 16 MPG combined. The Ferrari 458 Spider, its direct competitor, offers similar EPA ratings putting it in the same league as the SLS. These comparisons highlight the trade-offs in choosing the SLS, a car that prioritizes raw power and a uniquely thrilling driving experience over efficiency. These figures are important for potential buyers who may be cross-shopping or are looking at future ownership costs across all their vehicles.

Tips to maximize efficiency

While fuel efficiency isn’t the primary concern for SLS owners, there are a few strategies to minimize consumption without compromising the car’s character. Avoid unnecessary idling; the 6.2L V8 burns a surprising amount of fuel even when stationary.

Gentle acceleration and smooth braking can also have a measurable impact on fuel economy. The SLS is designed for spirited driving, modulating the throttle and anticipating traffic conditions will reduce fuel consumption.

Ensuring that the car is properly maintained, including regular tire pressure checks and fluid changes, can improve overall efficiency. Underinflated tires increase rolling resistance, while dirty engine oil can reduce engine performance.

Finally, consider using a fuel additive designed to improve fuel combustion. While anecdotal evidence varies, some additives can help to clean fuel injectors and improve fuel atomization, leading to slightly better fuel economy.

Explore all Mercedes Benz fuel economy data or view SLS MPG across all years to compare models.