22 MPG combined won’t wow anyone. But for the 2015 Mercedes-Benz E350 4matic wagon, it’s a reasonable trade-off. This vehicle isn’t about pinching pennies. It’s for drivers who want Mercedes-Benz refinement, wagon utility (especially an E-Class wagon), the grip of all-wheel drive, and the smooth power of a naturally aspirated V6. Fuel efficiency matters, but it’s secondary to those other features.

City and highway performance

The EPA estimates the E350 4matic wagon gets 20 MPG in the city and 26 MPG on the highway. Expect lower mileage in stop-and-go conditions, where the 3.5L V6 and 7-speed automatic transmission work harder. The highway number is better, showing the engine’s efficiency at consistent speeds and the transmission’s ability to select an overdrive gear. These aren’t great numbers, though, showing the powertrain’s age. Newer turbocharged engines often get better mileage without sacrificing performance.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2015 Mercedes-Benz E350 4matic wagon at $2,650. This is based on driving 15,000 miles per year and using national average fuel prices. Your actual costs will vary. Highway drivers will likely spend less than estimated, while city drivers will likely spend more.

Real-world expectations

Don’t count on consistently hitting the EPA numbers. The highway figure is reasonably reachable on long trips, but city and mixed driving will likely deliver slightly lower results. A realistic combined mileage might be 19-21 MPG. Aggressive driving, frequent short trips, and heavy loads will hurt fuel economy.

Proper maintenance is also important. Keeping tires inflated, ensuring the engine is tuned, and using recommended synthetic oil can help maintain good fuel efficiency.

How it compares

The 2015 E350 4matic wagon’s fuel economy isn’t as good as some competitors. A 2015 Audi A6 3.0T quattro sedan (not a wagon, but similarly priced) gets 24 MPG combined. Even some larger SUVs, like the Acura MDX with SH-AWD (21 MPG combined), come close. Looking at other Mercedes-Benz models, all Mercedes Benz fuel economy data, show more efficient models like the CLA250. The E350 4matic’s lower fuel economy stems from the older, naturally aspirated engine and the full-time all-wheel-drive system. Buyers considering an E350 MPG across all years should weigh its strengths against its efficiency.

Tips to maximize efficiency

Try the “ECO” mode, if equipped. This mode adjusts throttle response and shift points to prioritize fuel efficiency. The car might feel less responsive, but it can noticeably improve fuel consumption, particularly in the city.

Avoid hard acceleration and braking. Accelerate gently and brake smoothly to maximize fuel efficiency. Anticipate traffic and maintain a steady speed when possible. Every hard acceleration uses fuel, and hard braking wastes the energy you’ve already paid for.

Minimize idling. Modern engines don’t need long warm-ups. Excessive idling wastes fuel and increases emissions. If you’re stopped for more than a minute or two, turn off the engine.

Keep your tires inflated. Underinflated tires increase rolling resistance, reducing fuel efficiency. Check your tire pressure often and inflate them to the recommended pressure on the sticker on the driver’s side door jamb.

Reduce weight. Removing unnecessary items from the vehicle can slightly improve fuel economy. Extra weight increases the energy needed to accelerate and maintain speed. Lighter loads improve MPG, especially on the highway.