The 2020 Mercedes-Benz E450 4matic Convertible achieves a combined fuel economy rating of 22 MPG. This figure isn’t going to win any awards for efficiency, but let’s be honest: prospective buyers of this open-top luxury cruiser aren’t primarily concerned with squeezing every last mile from a gallon of premium. The E450 Convertible exists to provide a refined and exhilarating driving experience, and its fuel consumption is a calculated compromise within that mission.

City and highway performance

The EPA estimates for the E450 Convertible break down to 19 MPG in the city and 26 MPG on the highway. These figures indicate the car’s relaxed and torquey power delivery. The 3.0L inline-six, boosted by a turbocharger, provides ample power at low RPMs, which means less aggressive throttle input is needed in urban environments.

The 9-speed automatic transmission also plays a role, keeping the engine in its most efficient range possible without sacrificing responsiveness. On the highway, the E450’s aerodynamic profile and long gearing allow for comfortable and relatively economical cruising, provided the driver resists the urge to frequently unleash the engine’s full potential. Of course, with the top down, the temptation to accelerate is always present.

Annual fuel cost

According to the EPA, the annual fuel cost for the 2020 Mercedes-Benz E450 4matic Convertible is estimated at $2,650. This calculation is based on driving 15,000 miles per year and assumes current national average fuel prices.

It’s important to remember that this is just an estimate, and your actual fuel costs will vary depending on your driving habits, location, and fluctuations in gasoline prices. Someone who mainly drives short distances in stop-and-go traffic will likely exceed this figure, while someone who primarily takes long highway trips might see a slightly lower annual cost.

Real-world expectations

While the EPA provides a standardized benchmark, real-world MPG for the E450 Convertible will inevitably fluctuate. Drivers with a heavy foot or those who frequently engage in spirited driving can expect figures closer to the city rating, or even below. Conversely, careful drivers on long highway journeys might achieve numbers slightly better than the EPA’s 26 MPG estimate.

The overall MPG achieved will depend heavily on personal driving style, traffic conditions, and the percentage of city versus highway miles driven. Don’t expect hybrid-like efficiency, but also don’t assume you’ll be constantly visiting the gas station.

How it compares

In the realm of luxury convertibles, the E450’s fuel economy is fairly typical. The BMW 440i Convertible, for example, achieves an EPA-estimated 25 MPG combined, 22 city, and 32 highway with its inline-six. This is a significant advantage on the highway. A similarly equipped Audi S5 Cabriolet manages 24 MPG combined. These differences are often secondary considerations for buyers in this segment, but slightly more efficient alternatives exist if fuel consumption is a critical factor. If you want to look at all Mercedes Benz fuel economy data, you can see where the E450 lands in the lineup. You can also investigate E450 MPG across all years to see if another model year would better fit your needs.

Tips to maximize efficiency

Use the E450’s driving modes. The “Comfort” or “Eco” mode will prioritize fuel efficiency by adjusting throttle response, shift points, and other parameters. The “Sport” and “Sport+” modes offer a more engaging driving experience, and they also consume more fuel.

Maintain proper tire inflation. Underinflated tires increase rolling resistance, leading to lower fuel economy. Check your tires regularly and inflate them to the recommended pressure listed on the doorjamb or owner’s manual.

Avoid aggressive acceleration and braking. Smooth, gradual inputs are not only safer but also more fuel-efficient. Anticipate traffic conditions and avoid unnecessary hard stops, as this will help you conserve fuel.

Reduce unnecessary weight. Excess cargo in the trunk or back seats adds weight to the vehicle, which reduces fuel economy. Remove any items that you don’t need to carry on a regular basis.

Consider the type of fuel you use. While the E450’s engine is optimized for premium fuel, some owners might be tempted to use regular gasoline. Consult your owner’s manual to determine the recommended fuel type and stick to it, as using a lower octane fuel could negatively impact performance and fuel economy.