18 MPG combined isn’t going to win any awards, but it’s the price for the 2015 Infiniti Q70 AWD 5.6L. This isn’t a vehicle bought for its fuel sipping abilities. It’s a statement of power and luxury. Buyers want strong acceleration, comfortable cruising on long road trips, and the added security of all-wheel drive. Economy is a secondary consideration for those who end up behind the wheel of this particular Q70 variant.

City and highway performance

The EPA estimates the Q70 5.6L AWD achieves 16 MPG in the city and 23 MPG on the highway. The city figure reflects the demands of stop-and-go traffic, where the engine works harder to repeatedly accelerate the car’s considerable mass. The highway number, on the other hand, represents the potential for efficiency during steady-speed cruising. The seven-speed automatic transmission plays a role here, keeping the engine at lower RPMs once up to speed. But let’s be honest, a heavy foot will quickly negate any gains.

Annual fuel cost

The EPA estimates an annual fuel cost of $3,200 for the 2015 Infiniti Q70 AWD 5.6L. This calculation is based on driving 15,000 miles per year, using the EPA’s combined MPG figure, and assuming national average fuel prices. While the actual cost will vary depending on individual driving habits and local fuel prices, this number provides a standardized benchmark for comparison.

Real-world expectations

While the EPA estimates provide a useful baseline, real-world fuel economy often differs. You can expect to see figures close to the EPA’s numbers if you drive with a light foot and prioritize efficient driving habits. However, frequent bursts of acceleration to enjoy the engine’s power, combined with heavy city traffic, will likely pull the average down. Some owners have reported figures closer to the low-end of the EPA’s range, sometimes even dipping below it. The intoxicating V8 soundtrack comes at a price.

How it compares

The Q70 5.6L AWD lives in a competitive segment. The BMW 550i xDrive, for example, with its 4.4L V8, manages around 17 MPG combined. The Mercedes-Benz E550 4MATIC (also with a V8) exhibits comparable figures. Even the Lexus GS 350 AWD (V6) has an EPA rating of 22 MPG combined, illustrating the fuel penalty of a thirsty V8. For those prioritizing economy, the Q70 3.7L V6 offers a slightly better 21 MPG combined in its AWD configuration, available on Q70 MPG across all years. These comparisons are important for buyers weighing performance against efficiency in the luxury sedan market. You can find all Infiniti fuel economy data on our site.

Tips to maximize efficiency

The Q70 has a driver-selectable “Eco” mode. Engage this to remap the throttle response and shift points for maximum fuel efficiency. This setting will dampen acceleration, encouraging a more gentle driving style that allows the engine to operate in its most economical range.

Tire pressure is critical. Ensure your tires are properly inflated to the recommended pressure, which can be found on a sticker inside the driver’s side doorjamb. Underinflated tires increase rolling resistance, forcing the engine to work harder and burning more fuel.

Avoid excessive idling. If you’re stopped for more than a minute, turn off the engine. Modern engines are designed to restart quickly and efficiently, and excessive idling wastes fuel without contributing to range.

Plan your routes strategically. Avoiding congested areas and stop-and-go traffic can significantly improve fuel efficiency. Using a navigation system with real-time traffic updates can help you find the most efficient route, saving both time and fuel.

Gentle acceleration and braking are key to minimizing fuel consumption. Avoid aggressive driving habits, which dramatically increase fuel use. Smooth and progressive inputs to both the accelerator and brake pedal will yield better results in the long run.