Mercedes-Benz · 2017
C300 Convertible 2.0L 4-cyl
✓ EPA Verified
Premium Gasoline
Subcompact Cars
Rear-Wheel Drive
City
23
MPG
Combined
26
MPG
Highway
31
MPG
Annual Fuel Cost
$2,250
Based on 15,000 miles/year · EPA estimates
vs avg gas vehicle
$100
more per year
Class Comparison — Subcompact Cars
Top 32%
Better than 68 out of 100 vehicles in its class for fuel efficiency.
This vehicle: 26 MPG
This vehicle
26 MPG
Class average
27 MPG
Class lowest
12 MPG
EPA Energy & Environment Scores
6
Energy Score
Out of 10
6
GHG Score
Out of 10
342 lbs
Annual CO₂
g/mile tailpipe CO₂
Yes
Start-Stop
Auto stop-start
Vehicle Specifications
Engine2.0L 4-cyl
TransmissionAutomatic 9-spd
DriveRear-Wheel Drive
Fuel TypePremium Gasoline
Vehicle ClassSubcompact Cars
Engine DescSIDI
Start-StopYes
EPA Vehicle ID38141

The 2017 Mercedes-Benz C300 Convertible, equipped with its 2.0L 4-cylinder engine, achieves a combined EPA rating of 26 MPG. This is a luxury open-air vehicle. The C300 Convertible prioritizes style and brand appeal. Its buyers understand that four-seat convertibles, especially those bearing the Mercedes-Benz star, involve some sacrifices to fuel economy.

City and highway performance

The C300 Convertible’s EPA ratings break down to 23 MPG in the city and 31 MPG on the highway. The city number is particularly relevant because this car is frequently used for short, stylish trips around town, such as dinner dates, weekend shopping, and salon visits. The 31 MPG highway figure is respectable, making longer weekend getaways feasible without constant gas station anxiety. This balance reflects careful engineering from Mercedes-Benz, with the 9-speed automatic transmission playing an important role in optimizing both acceleration and fuel efficiency by keeping the engine in its most efficient range whenever possible. The turbocharger also contributes.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2017 Mercedes-Benz C300 Convertible at $2,250. This calculation is based on driving 15,000 miles per year, using the EPA’s projected fuel consumption, and factoring in national average gasoline prices. This is an average, and actual spending depends heavily upon location, driving habits, and the prevailing price of premium fuel, which is recommended for optimal performance in the C300.

Real-world expectations

While the EPA provides a standardized benchmark, real-world fuel economy often varies. Expect the C300 Convertible to deliver figures close to the EPA estimates under normal driving conditions. Aggressive acceleration, frequent use of Sport mode, and extended idling can significantly reduce fuel efficiency. Conversely, a conscious effort to drive smoothly and use the available Eco mode can help achieve or even slightly exceed the EPA ratings. Keep your tires properly inflated to ensure optimal rolling resistance.

How it compares

The C300 Convertible competes in a segment where fuel economy isn’t always the primary concern. The BMW 430i Convertible, another popular choice, delivers around 27 MPG combined. The Audi A5 Cabriolet manages around 26 MPG combined. These slight differences are unlikely to sway a buyer heavily in one direction or another, the decision typically comes down to styling preference, brand loyalty, and the specific features offered. However, the C300 Convertible isn’t drastically different from its direct competitors, which helps buyers manage their expectations. Compare C300 MPG across all years.

Tips to maximize efficiency

Given the C300’s turbocharged engine, avoid aggressive acceleration. The turbocharger enhances power but consumes more fuel when heavily used. Gentle acceleration and maintaining a steady speed on the highway will significantly improve fuel economy.

Use the C300’s drive mode selector. Eco mode prioritizes fuel efficiency by adjusting throttle response and transmission behavior. While it might slightly reduce responsiveness, it’s an effective way to save fuel during everyday driving, especially in stop-and-go traffic.

Regular maintenance is critical for optimal fuel economy. Ensure your C300 receives timely oil changes, air filter replacements, and spark plug maintenance. A well-maintained engine operates more efficiently, resulting in better MPG. Consult all Mercedes Benz fuel economy data to help guide you.

Pay attention to tire inflation. Underinflated tires increase rolling resistance, forcing the engine to work harder and consume more fuel. Check tire pressure regularly and inflate them to the recommended levels specified on the doorjamb sticker, not just to the maximum pressure on the tires themselves.