21 MPG combined isn’t going to win any fuel efficiency awards, but for the long-wheelbase, V8-powered Audi A8 L, it’s an acceptable trade-off for the effortless performance and luxury. Buyers in this segment, typically captains of industry, executives, and those who prioritize rear-seat space and in-car technology, understand that thrift is not the main objective. They seek a refined driving experience, a comfortable and spacious cabin, and the prestige of owning a top-tier luxury vehicle. For these buyers, the A8 L’s fuel consumption is simply a cost of doing business.

City and highway performance

The 2015 Audi A8 L 4.0L V8 achieves 18 MPG in the city and 29 MPG on the highway. The city figure reflects the engine’s thirst when navigating stop-and-go traffic, despite features like cylinder deactivation, which shuts down cylinders under light load to conserve fuel. The highway figure is where this powertrain performs well. The A8 L’s smooth eight-speed automatic transmission and aerodynamic design allow for relaxed and efficient cruising at higher speeds. This makes it well-suited for long-distance travel, where its occupants can enjoy the luxurious interior and quiet ride.

Annual fuel cost

The EPA estimates that the annual fuel cost for the 2015 Audi A8 L 4.0L V8 is $2,750. This figure is based on driving 15,000 miles per year and using national average fuel prices. While the actual cost will vary depending on individual driving habits and fuel prices in your area, it provides a useful benchmark for comparing the fuel expenses of different vehicles. Luxury cars often require premium fuel, which adds to the overall expense. This annual cost must be considered within the context of the A8 L’s overall price tag and running costs, which are generally higher than those of more economical vehicles.

Real-world expectations

While the EPA figures offer a standardized estimate, real-world fuel economy can vary. Factors such as driving style, traffic conditions, and even tire pressure can impact the fuel consumption of the A8 L. Aggressive acceleration and frequent hard braking will decrease fuel economy, while a relaxed and consistent driving style will help achieve results closer to the EPA estimates. Regularly servicing the car, including ensuring proper tire inflation and engine maintenance, will also contribute to optimal fuel efficiency. To understand the typical results that A8 owners achieve, explore A8 MPG across all years on various online forums and fuel tracking apps to gain information.

How it compares

In the realm of flagship luxury sedans, the A8 L’s fuel economy is competitive, but not class-leading. The BMW 750Li xDrive, with its 4.4L V8, achieves similar EPA ratings, around 17 MPG city and 26 MPG highway. The Mercedes-Benz S550, also powered by a V8, posts numbers in the same ballpark. The Lexus LS 460 L could be considered a more fuel-efficient option, but its naturally aspirated V8 provides a different driving experience, that some find less thrilling than the A8’s turbocharged engine. A modern hybrid like a Lexus LS 500h, will easily eclipse the A8 L’s efficiency, often achieving over 30 MPG combined, but it trades some outright performance for that efficiency. These comparisons matter to the A8 L buyer who is at least somewhat conscious of fuel consumption. Fuel consumption isn’t the primary decision factor, they want to know that they’re not drastically worse off than the competition.

Tips to maximize efficiency

Using “drive select” to engage the “efficiency” or “comfort” mode can soften throttle response and optimize the transmission for better fuel economy. This mode encourages smooth acceleration and earlier upshifts, which helps to conserve fuel, particularly in stop-and-go traffic.

Ensure that your tires are properly inflated to the recommended pressure. Low tire pressure increases rolling resistance, forcing the engine to work harder and consuming more fuel. Check your tire pressure regularly, especially during temperature changes.

Avoid unnecessary idling. If you’re stopped for more than a minute, it’s generally more fuel-efficient to turn off the engine. Modern engines are designed to restart quickly and efficiently, so idling for extended periods is simply wasting fuel.

Minimize the use of accessories like air conditioning and heated seats when they’re not essential. These features put an extra load on the engine, which can negatively impact fuel economy, particularly at lower speeds.

Regularly check and replace air filters. A clogged air filter restricts airflow to the engine, which can reduce fuel economy. A clean air filter helps the engine breathe easier, improving performance and efficiency. If you are looking to explore all Audi models and their fuel consumption, review all Audi fuel economy data.