23 MPG combined isn’t going to win any hypermiling contests, but it’s a perfectly reasonable figure for what the 2015 Mercedes-Benz E350 is: a refined, comfortable, and surprisingly capable luxury sedan. The E350 isn’t pitched as an economy car, nor is it usually cross-shopped against one. Its efficiency is a secondary consideration to buyers who value its build quality, ride comfort, and classic Mercedes-Benz sensibility. They are willing to accept middling MPG in exchange for the rest of the package.

City and highway performance

The E350’s 3.5L V6 manages a respectable 20 MPG in the city. This isn’t bad for a naturally aspirated six-cylinder engine powering a car of this size. The 7-speed automatic transmission helps keep the engine in its sweet spot, balancing responsiveness with efficiency. On the highway, the E350 fares better, achieving 28 MPG. This showcases the benefits of the transmission’s overdrive gears and the engine’s ability to cruise comfortably at highway speeds without significant fuel consumption. This figure also makes long road trips financially reasonable, because many E350 owners use their cars to travel frequently.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2015 Mercedes-Benz E350 at $2,500. This figure is based on driving 15,000 miles per year and using the national average fuel price for premium unleaded gasoline, which is the recommended fuel for optimal performance and engine longevity. It represents a full year of fuel costs for the average driver. Keep in mind that this number is sensitive to fluctuations in gas prices and individual driving habits.

Real-world expectations

While the EPA numbers provide a useful benchmark, real-world fuel economy can vary a lot. Aggressive driving, stop-and-go traffic, and even tire pressure can all impact the MPG you achieve. Owners who prioritize smooth acceleration, anticipate traffic flow, and maintain their vehicles meticulously are more likely to see figures closer to the EPA estimates. Drivers who enjoy the E350’s eager throttle response and spend more time in congested areas may find themselves slightly below the official MPG numbers. Check out E350 MPG across all years to see reported mileage from other drivers.

How it compares

Compared to its competitors, the 2015 E350’s fuel economy is in line with expectations for its segment. The BMW 535i, with its turbocharged inline-six, achieves roughly the same combined MPG. The Audi A6 3.0T, with its supercharged V6, also posts similar fuel economy figures. The Lexus GS 350 is slightly more efficient, often getting a 1-2 MPG advantage. These differences, however, are often negligible to the E350 buyer, who prioritizes the driving feel and brand cachet of the Mercedes-Benz over a small fuel saving. For a wider view of the brand’s efficiency, review all Mercedes Benz fuel economy data.

Tips to maximize efficiency

Avoid aggressive acceleration. The E350’s V6 offers ample power, but stomping on the gas pedal will drastically reduce fuel economy. Instead, aim for smooth, progressive acceleration, allowing the transmission to shift efficiently. The car’s strong torque means you don’t need to bury the throttle to get moving, so trust the engine to do its job and resist the urge to floor it.

Ensure your tires are properly inflated for optimal rolling resistance. Check the sticker on the driver’s side doorjamb for the recommended tire pressure. Underinflated tires create more friction, decreasing fuel economy. Regular tire pressure checks are a simple way to improve your MPG and extend the life of your tires.

Use cruise control on the highway. Maintaining a consistent speed not only improves fuel economy but also reduces driver fatigue on long journeys. The E350 is designed for quiet cruising, and cruise control allows the engine to operate at its most efficient.

Minimize idling. If you anticipate waiting for more than a minute or two, turn off the engine. Idling consumes fuel without covering any distance. Modern engines are designed to restart quickly and efficiently, so there is no significant wear and tear associated with turning off the engine during short stops.