22 MPG combined won’t win any hypermiling competitions, but for the 2018 Mercedes-Benz E400 4matic Coupe, it’s an understandable compromise. This isn’t a car purchased solely for maximizing fuel efficiency; it’s a statement. It’s a blend of style, performance, and luxury that prioritizes driver experience over frugality. The buyer in this segment is likely a professional, perhaps a lawyer or executive, someone who appreciates the finer things and needs a car that reflects their success without sacrificing driving enjoyment.

City and highway performance

The EPA estimates the E400 Coupe gets 20 MPG in the city and 26 MPG on the highway. The city figure reflects stop-and-go traffic, where the 3.0L twin-turbo V6 engine and 9-speed automatic transmission work harder. The engine’s power delivery is smooth and responsive, encouraging spirited driving, which can further impact city MPG.

On the highway, the E400 Coupe cruises comfortably, thanks to the 9-speed transmission allowing the engine to operate at lower RPMs. Achieving the 26 MPG rating is possible, particularly on long, flat stretches where the all-wheel-drive system isn’t heavily engaged.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2018 Mercedes-Benz E400 4matic Coupe at $2,650. This calculation is based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway, using the national average fuel prices at the time of calculation. It’s a benchmark, and your actual fuel costs will vary depending on your driving habits, the type of fuel you use, and fluctuating gas prices. Premium fuel is recommended for optimal performance, which will contribute to the annual expense. See E400 MPG across all years for changes over time.

Real-world expectations

While the EPA numbers provide a baseline, real-world fuel economy often differs. Aggressive driving, frequent short trips, and heavy reliance on the air conditioning can all decrease the MPG. Conversely, conservative driving techniques and prioritizing highway miles can improve it. Expect to see figures close to the EPA estimates if you are mindful of your driving style.

Some owners report slightly better highway numbers when consistently driving at or below the speed limit. The all-wheel-drive system, while providing added traction and stability, does add weight and complexity, which can subtly reduce fuel efficiency compared to rear-wheel-drive counterparts.

How it compares

The E400 Coupe is in a competitive segment, with several alternatives offering similar blends of luxury and performance. The BMW 440i xDrive Coupe, for instance, offers a combined EPA rating of 25 MPG, giving it a slight edge in fuel efficiency. The Audi A5 Coupe Quattro achieves a combined EPA of 27 MPG with its 2.0T engine. These figures highlight that some competitors prioritize less gas. The E400 Coupe’s appeal is its unique blend of Mercedes-Benz styling, refined interior, and potent V6 engine. Owners may accept slightly lower fuel economy for these attributes.

Tips to maximize efficiency

Maintain a smooth and steady driving style. Avoid hard acceleration and braking, as these actions significantly impact fuel consumption. The E400’s 9-speed transmission is designed to keep the engine in its most efficient range, so let it do its job.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, forcing the engine to work harder and consume more fuel. Check your tire pressure regularly and inflate them to the recommended pressure listed on the doorjamb.

Reduce unnecessary weight. Carrying excessive cargo in the trunk or back seat adds weight to the vehicle, decreasing fuel efficiency. Remove any items that you don’t need to carry regularly.

Plan your routes strategically. Avoid peak traffic hours whenever possible to minimize stop-and-go driving. Using navigation apps to identify routes with less congestion can help improve fuel economy.

Consider using the ECO drive mode if equipped. This mode typically adjusts the throttle response, transmission shift points, and climate control settings to prioritize less gas. While it may slightly reduce performance, it can contribute to improvements in MPG. See all Mercedes Benz fuel economy data.