18 MPG combined isn’t going to win any fuel efficiency awards, and nobody buying a 2016 Audi S8 4.0L 8-cyl expects it to. This is a brutally fast, supremely comfortable Autobahn missile disguised as a sensible sedan. Efficiency is simply not its main focus. The S8 is purchased by executives, entrepreneurs, and enthusiasts who prioritize effortless power and understated luxury over saving money at the pump.

City and highway performance

The EPA estimates for the 2016 S8 are 15 MPG in the city and 25 MPG on the highway. The city number reflects the engine’s tendency to consume fuel when accelerating frequently from a standstill, common in urban environments. The highway figure, while still not exceptional, is more palatable, suggesting the S8 can at least cruise efficiently when not being pushed. However, resist the urge to fully unleash the 520 horsepower twin-turbo V8 and you’ll likely see figures closer to the official ratings.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2016 Audi S8 at precisely $3,200. This figure is based on driving 15,000 miles per year, with 55% of those miles driven in the city and 45% on the highway. The calculation also relies on the national average fuel price at the time of estimation, which fluctuates but provides a standardized benchmark. For S8 owners, this cost is simply part of the price of admission to a world of exhilarating performance and refined luxury.

Real-world expectations

While the EPA estimates provide a baseline, real-world fuel economy for the 2016 S8 will vary based on driving style and conditions. Aggressive acceleration, frequent short trips, and prolonged idling will all noticeably reduce fuel efficiency. Conversely, smooth, consistent highway driving can potentially yield figures exceeding the 25 MPG estimate. Drivers residing in areas with hilly terrain or frequent traffic congestion should also anticipate lower MPG averages. Consult S8 MPG across all years for further variations across the model’s production run.

How it compares

The 2016 S8’s fuel economy lags behind many of its competitors, but not by a dramatic margin. The BMW 750i, with its 4.4L V8, manages a slightly better 17 MPG city and 26 MPG highway. A Mercedes-Benz S550, despite its comparable power, achieves around 17 MPG city and 26 MPG highway. Even the Porsche Panamera 4S, a sportier alternative, offers similar fuel consumption in real world use. The Audi appeals to buyers who value its specific blend of understated styling, all-weather capability (thanks to Quattro all-wheel drive), and blistering acceleration, characteristics that often outweigh a marginal difference in fuel costs. Browse all Audi fuel economy data for a comparison across their entire model line.

Tips to maximize efficiency

Take advantage of the Audi Drive Select system. Choosing the “Efficiency” mode will adjust throttle response, transmission mapping, and climate control settings to prioritize fuel conservation. This mode is most effective during steady-state highway cruising where instantaneous power isn’t needed.

Monitor your tire pressure regularly. Underinflated tires increase rolling resistance, which directly impacts fuel economy. The S8’s tire pressure monitoring system will alert you to significant pressure drops, but a manual check ensures optimal inflation levels are maintained.

Avoid unnecessary idling. The S8’s V8 engine consumes a considerable amount of fuel even when stationary. If you anticipate being stopped for more than a minute or two, it’s best to turn off the engine to conserve fuel. This is particularly relevant in urban environments with frequent traffic lights.

Use cruise control on the highway whenever possible. Maintaining a consistent speed minimizes unnecessary acceleration and deceleration, which are major contributors to fuel inefficiency. Set the cruise control to a reasonable speed and let the S8’s advanced driver assistance systems help you maintain a safe following distance.

Anticipate traffic flow to the best of your ability. By looking ahead and predicting changes in traffic speed, you can minimize abrupt braking and acceleration. Smooth, gradual transitions are far more fuel-efficient than jerky stop-and-go driving. This becomes easier with practice and familiarity with your regular commute.