18 MPG combined. That’s the number on the fuel economy sticker of the 2021 Ford Mustang Convertible with the snarling 5.0L V8. It’s not great. But for the person driving this car, fuel efficiency is often less important than the burbling exhaust or the wind in their hair when driving on backroads. This is a muscle car, made to deliver a visceral experience, and for many Mustang buyers, the fuel bill is simply the cost of admission.

City and highway performance

The EPA estimates for the 2021 Mustang Convertible 5.0L auto are 15 MPG in the city and 23 MPG on the highway. The city figure reflects stop-and-go traffic, where the big V8 is constantly working. On the open road, with the transmission in a higher gear, the Mustang is surprisingly efficient. 23 MPG isn’t bad for a large engine in a heavy car. But few buy a 5.0L Mustang for quiet highway cruising.

Annual fuel cost

According to the EPA, the annual fuel cost for the 2021 Ford Mustang Convertible 5.0L is $2,450. This is based on driving 15,000 miles per year, with a mix of city and highway driving, and using the EPA’s estimate of national average fuel prices. Your costs will vary depending on your driving and where you live. If you spend most of your time in traffic or drive aggressively, expect to exceed that amount.

Real-world expectations

The EPA numbers provide a baseline, but real-world fuel economy often differs. Aggressive acceleration, spirited driving, and prolonged idling can all impact your MPG. Some drivers report lower numbers than the EPA estimates when enjoying the 5.0L V8. Careful drivers who prioritize fuel efficiency can sometimes match or slightly exceed the highway estimate. Few Mustang owners are buying this car to set fuel economy records.

How it compares

The 2021 Mustang Convertible 5.0L’s fuel economy is similar to other V8-powered convertibles. A Chevrolet Camaro Convertible with the 6.2L V8 achieves a similar 16 MPG city and 24 MPG highway. Even the four-cylinder Mustang EcoBoost Convertible manages only 20 MPG combined, showing the penalty for the V8 sound and performance. For better fuel economy in a convertible, consider a Mazda MX-5 Miata, which achieves around 30 MPG combined, but offers a different driving experience and power. Specific Mustang MPG data across all years is available online. You can also review all Ford fuel economy data for more perspective.

Tips to maximize efficiency

Fuel efficiency might not be the primary goal, but you can minimize fuel consumption in your 2021 Ford Mustang Convertible 5.0L. Avoid rapid acceleration and hard braking. The 5.0L engine rewards a smooth driving style with better fuel economy.

Ensure your tires are properly inflated. Underinflated tires increase rolling resistance, forcing the engine to work harder. Check your tire pressure regularly and inflate them to the level on the sticker inside the driver’s side doorjamb.

Minimize idling. Idling wastes fuel, especially in a large engine. If you’re stopped for more than a minute or two, turn off the engine. Modern starters are made to handle frequent starts.

Use cruise control on the highway. Maintaining a consistent speed can improve fuel economy. Be mindful of traffic and ready to disengage cruise control when needed.

Keep up with regular maintenance. A well-maintained engine runs more efficiently. Follow the maintenance schedule for your Mustang, including oil changes, air filter replacements, and spark plug replacements.