24 MPG combined isn’t going to win any awards in the fuel efficiency department, but for the 2023 BMW 840i xDrive Convertible, it’s not the main attraction. This isn’t a car bought for its frugality; it’s a statement of style, performance, and open-air motoring. The customer is more likely to prioritize the thrill of a turbocharged inline-six and the admiring glances the sleek convertible gets than getting every last mile from a gallon of premium fuel. They accept the fuel costs as a necessary lifestyle tax.

City and highway performance

The EPA estimates 21 MPG in the city and 29 MPG on the highway. The city figure reflects the realities of urban driving, where the 840i’s weight and powerful engine demand more fuel during frequent acceleration. The highway number, however, shows the engine’s efficiency at cruising speeds. The eight-speed automatic transmission helps keep the engine in its sweet spot, balancing power with fuel consumption. The temptation to use the turbocharged engine’s power can easily lower the highway figure.

Annual fuel cost

The EPA calculates the annual fuel cost for the 2023 BMW 840i xDrive Convertible at $2,400. This is based on driving 15,000 miles per year, with fuel prices reflecting the national average for premium gasoline. Your actual fuel costs will vary depending on your driving, the type of driving you do, and local fuel prices. Someone using the 840i primarily for weekend pleasure cruises will likely spend less, while a driver with a heavy foot and a long commute can expect to exceed that $2,400 figure.

Real-world expectations

While the EPA provides a benchmark, real-world fuel economy often differs. Owners of the 840i Convertible report figures that generally align with, or are slightly below, the EPA estimates.

Aggressive acceleration, frequent use of the Sport mode, and extended idling in traffic can all negatively impact fuel efficiency. Mindful driving with a light foot and using the Eco Pro mode on longer highway trips can yield results closer to the EPA ratings. How you drive this car matters far more to the MPG you get than how you might drive a family sedan.

How it compares

The 840i Convertible occupies a niche space, but comparisons can be made with other luxury convertibles. The Mercedes-Benz SL 55 AMG offers more power but achieves around 16 MPG city and 24 MPG highway, making it a thirstier choice. The Porsche 911 Carrera Cabriolet, depending on the specific engine configuration, can deliver slightly better fuel economy, with some models reaching close to 20 MPG city and 26 MPG highway. The 911 has a steeper price tag. Understanding all Bmw fuel economy data alongside the competition helps buyers weigh their priorities. The 840i convertible prioritizes luxury and performance and finds itself in the middle of the range where fuel consumption is concerned. You can compare its ratings to the 840I MPG across all years as well.

Tips to maximize efficiency

Engage Eco Pro mode whenever possible, particularly during highway driving. This mode adjusts throttle response and shift patterns to prioritize fuel efficiency, reducing performance a little to save fuel. It won’t turn the 840i into a Prius, but it can make a noticeable difference on longer trips.

Maintain a steady speed on the highway. Accelerating and decelerating frequently consumes more fuel. Using cruise control can help maintain a consistent speed and optimize fuel consumption, especially on flatter roads. Try to anticipate traffic and avoid unnecessary braking.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, which reduces fuel efficiency. Check your tire pressure regularly and inflate them to the recommended pressure listed on the doorjamb sticker. This improves fuel economy and extends tire life.

Minimize idling time. Letting the engine idle wastes fuel. If you’re stopped for more than a minute, turn off the engine. Modern engines are designed to start quickly and efficiently, so restarting isn’t as detrimental as it once was.

Schedule regular maintenance. A well-maintained engine runs more efficiently. Follow the manufacturer’s recommended maintenance schedule for oil changes, filter replacements, and other services. This ensures optimal performance and fuel economy and extends the life of the vehicle.