23 MPG combined won’t win any fuel economy awards, but for the 2021 BMW 840i xDrive Gran Coupe, it’s an accepted compromise for the performance, style, and driving experience. This isn’t a vehicle for penny-pinchers. The 840i Gran Coupe caters to buyers who prioritize a sleek, luxurious four-door with ample power and all-weather confidence, even if it means less gas than a Prius.

City and highway performance

The EPA estimates that the 840i xDrive Gran Coupe will achieve 20 MPG in the city and 27 MPG on the highway. The city figure reflects the stop-and-go nature of urban driving, where the car’s weight and the frequent acceleration phases impact fuel economy. The highway number, while better, is still relatively modest given the car’s turbocharged 3.0-liter inline-six engine. This engine provides ample power for effortless cruising, but even with BMW’s engineering, aerodynamic drag and rolling resistance limit efficiency at higher speeds. The smooth-shifting eight-speed automatic transmission (S8) helps optimize fuel economy at different speeds, but it can only do so much when paired with a powerful engine in a relatively large vehicle. Take a look at 840I MPG across all years to see how this model compares.

Annual fuel cost

According to the EPA, the annual fuel cost for the 2021 BMW 840i xDrive Gran Coupe is estimated at $2,500. This figure is based on driving 15,000 miles per year and using the EPA’s projected national average fuel prices. Keep in mind that premium fuel is required for optimal performance and longevity and that likely factors into the substantial annual cost. This means that individuals who drive more than 15,000 miles annually or experience higher-than-average fuel prices in their region will likely face even greater fuel expenses.

Real-world expectations

While the EPA estimates provide a baseline, real-world fuel economy can vary significantly depending on driving style, traffic conditions, and climate. Expect numbers that fluctuate around the EPA estimates. Aggressive acceleration, frequent hard braking, and extended idling will all negatively impact fuel efficiency. Cold weather or mountainous terrain will also likely reduce MPG. Owners who prioritize fuel efficiency and adopt a smoother driving style may be able to achieve figures closer to the EPA highway estimate, even in mixed driving conditions.

How it compares

Against other four-door coupes in the luxury segment, the 840i xDrive Gran Coupe’s fuel economy is reasonably competitive, though not class-leading. The Mercedes-Benz CLS 450 4MATIC, for example, achieves a similar 22 MPG combined, while offering comparable performance and luxury. The Audi A7, in its 55 TFSI guise, manages about 24 MPG combined. The Porsche Panamera, particularly in its base configuration, might offer slightly better fuel economy around 25 MPG combined, but it also commands a higher price tag. The fact that the 840i achieves similar economy to its rivals despite offering xDrive all-wheel drive should be taken into account. For comparison, examine all BMW fuel economy data.

Tips to maximize efficiency

Avoid aggressive starts and stops. The 840i Gran Coupe’s powerful engine responds beautifully to a light touch on the accelerator. Gentle acceleration enhances fuel economy and contributes to a smoother, more refined driving experience. Smooth and steady is effective.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, which directly impacts fuel consumption. Check your tire pressures regularly and maintain them at the recommended levels, typically found on a sticker inside the driver’s side door jamb. This also ensures optimum tire wear.

Minimize idling. Idling consumes fuel without any forward progress. If you anticipate being stationary for more than a brief period, such as at a long traffic light or waiting for someone, turn off the engine. The 840i has a quick restart system, making this process relatively efficient.

Take advantage of driving modes. The 840i offers various driving modes, including an “Eco Pro” mode. Selecting this mode optimizes various vehicle settings, such as throttle response and transmission mapping, to prioritize fuel efficiency. Use this mode when maximum fuel economy is desired, especially on longer highway journeys.