18 MPG combined isn’t going to win any awards, but it’s the price of admission for driving the 2016 Mercedes-Benz AMG CLS63 S 4matic. This isn’t a car bought by drivers prioritizing fuel savings. They’re after brutal acceleration, a handcrafted interior, and the prestige that comes with the AMG badge. For these buyers, 18 MPG is simply a detail they accept while enjoying a visceral driving experience few other sedans can match.

City and highway performance

The EPA estimates the CLS63 S 4matic at 16 MPG in the city and 22 MPG on the highway. That discrepancy speaks volumes. The city figure reflects the toll that stop-and-go traffic takes even on efficient cars, and it is made worse with a twin-turbocharged 5.5L V8 that’s always itching to unleash its fury. The highway figure is slightly more palatable, indicating that with careful throttle management on longer cruises, you can approach the EPA’s estimation and not have to stop for fuel every 200 miles. But let’s be honest, “careful throttle management” isn’t exactly what attracts people to this vehicle.

Annual fuel cost

The EPA calculates the annual fuel cost for the 2016 Mercedes-Benz AMG CLS63 S 4matic at $3,200. This is based on driving 15,000 miles per year and using national average fuel prices for premium gasoline. Keep in mind that fluctuations in gas prices directly impact this figure; living in an area with high fuel costs will increase your expenditure. It is a sobering thought, though most AMG owners already knew to expect this.

Real-world expectations

While the EPA provides a benchmark, real-world MPG for the CLS63 S varies widely based on driving style. Owners who frequently exploit the engine’s capabilities will likely see figures significantly lower than 18 MPG. Conversely, those who primarily use the car for highway commuting and drive with a lighter foot might achieve slightly better numbers. The temptation to experience the car’s performance is strong, though. Even if you try to be mindful of your fuel usage, the occasional burst of acceleration is almost unavoidable.

How it compares

The CLS63 S doesn’t exactly have a reputation as an economy car, and its competitors don’t fare much better. The 2016 BMW M6 Gran Coupe, another powerful four-door coupe, manages a similar 17 MPG combined. The Audi RS 7 posts an identical 18 MPG combined. These numbers demonstrate that performance at this level comes at a fuel economy cost. Someone deciding between these cars likely views MPG as a secondary factor, with performance, luxury, and brand image taking precedence. See all Mercedes Benz fuel economy data, or browse AMG MPG across all years to see the variations across the brand’s performance-focused vehicles.

Tips to maximize efficiency

While hypermiling isn’t exactly in the spirit of owning an AMG, there are still ways to improve fuel economy without sacrificing all the fun. Gentle acceleration from a stop can make a difference. That twin-turbo V8 gobbles fuel when pushed hard from a standstill, so easing into the throttle can noticeably reduce consumption, especially in city driving.

Cruise control is your friend on the highway. Maintaining a steady speed minimizes unnecessary acceleration and deceleration, optimizing fuel efficiency on longer trips. Resist the urge to constantly overtake slower traffic, as each burst of speed eats directly into your MPG.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, forcing the engine to work harder and use more fuel. Check your tire pressure regularly and inflate them to the recommended levels, usually found on a sticker inside the driver’s side door jamb.

Consider using a fuel additive designed to clean fuel injectors. Clean injectors atomize fuel more efficiently, contributing to better combustion and potentially improving fuel economy. This is particularly important on vehicles that are driven enthusiastically, as carbon buildup can affect injector performance.