24 MPG combined won’t win any fuel efficiency awards, but for the 2015 BMW 640i Convertible, it’s almost beside the point. This isn’t a car for practical commuters. It’s for those who want open-air thrills and effortless performance. The 640i Convertible is a statement, a reward, an escape, and its MPG reflects that driving pleasure is more important than saving gas.

City and highway performance

The EPA estimates the 2015 BMW 640i Convertible gets 20 MPG in the city and 30 MPG on the highway. In urban environments, the turbocharged 3.0-liter inline-six needs more throttle to navigate stop-and-go traffic, which affects fuel consumption. On the open road, the 640i’s long gearing and refined aerodynamics let it cruise comfortably and efficiently, getting close to that 30 MPG figure easily. The eight-speed automatic transmission helps in both situations, offering smooth shifts and optimized gear ratios for every driving scenario.

Annual fuel cost

The EPA estimates the annual fuel cost at $2,400 for the 2015 BMW 640i Convertible. This is based on driving 15,000 miles per year and using national average fuel prices. Remember that premium fuel is recommended for best performance, so include that in your gas budget. Your driving habits, local fuel costs, and the amount of city versus highway driving will all change how much you spend on fuel, and most 640i owners won’t mind paying a bit more at the pump to drive this car.

Real-world expectations

EPA numbers are a starting point, but real-world fuel economy can change. Drivers who accelerate quickly or often push the 640i’s performance are likely to see lower numbers, possibly below 20 MPG. However, those who drive more carefully and spend more time on the highway could see numbers closer to, or even a bit higher than, the EPA estimates. It’s unlikely that most owners will be closely tracking their fuel consumption, especially knowing all all Bmw fuel economy data is available on the web.

How it compares

Compared to other luxury convertibles of its time, the 640i is competitive. The Mercedes-Benz E400 Convertible, with a turbocharged six-cylinder engine, achieves similar fuel economy at about 20 MPG city and 29 MPG highway. The Audi S5 Cabriolet, with a supercharged V6, gets a bit less, usually around 18 MPG city and 26 MPG highway. Even considering the 640I MPG across all years, The 640i balances performance and efficiency. This makes it a good choice for those who want a luxurious and fun open-top experience without completely ignoring fuel economy.

Tips to maximize efficiency

Use the car’s driving mode selector. The “Eco Pro” mode changes vehicle settings, like throttle response and shift points, to use less gas. It might make the 640i less sporty, but it can help during regular commutes.

Avoid fast acceleration and hard braking. Smooth, steady driving is important for fuel economy in any car, and the 640i is no different. Watch the traffic and drive at a consistent speed. A measured driving style has a high impact because of the large engine and strong horsepower.

Make sure your tires are properly inflated. Underinflated tires increase rolling resistance, which lowers fuel efficiency. Check your tire pressure often and inflate them to the recommended levels, which are usually on a sticker inside the driver’s side doorjamb, if you want to get a few more miles per gallon.

Use air conditioning less. The air conditioning compressor puts stress on the engine, which reduces fuel economy. Open the convertible top when the weather is nice to enjoy the open air without losing fuel efficiency. With the top down, there’s much less resistance which helps the engine.

Follow the scheduled maintenance. Regular oil changes, air filter replacements, and other maintenance ensure your 640i runs well and efficiently. A well-maintained engine runs smoothly and uses less gas.