16 MPG combined is the stark reality for anyone considering a 2015 Infiniti QX80 4WD with the 5.6L V8. Let’s be clear: this is not a vehicle purchased for its frugality. It is a rolling monument to capability, a luxurious brute designed to haul families and tow trailers with equal aplomb. The fuel consumption is simply part of the price. a price those who need what the QX80 offers are typically prepared to pay.

City and highway performance

The EPA estimates put the QX80 at 14 MPG in the city and 20 MPG on the highway. The discrepancy highlights the engine’s thirst when dealing with stop-and-go traffic and the vehicle’s prodigious weight. On the open road, with consistent speeds and minimal acceleration, the QX80’s efficiency improves somewhat, but those numbers are still sobering. Much of this comes down to the naturally aspirated 5.6L V8, a strong but ultimately old-school engine that prioritizes power over pinpoint fuel management. Its partner, a 7-speed automatic transmission, tries to make the most of available torque, but even that can’t fully compensate for the laws of physics.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2015 Infiniti QX80 4WD at precisely $3,600. This figure is based on driving 15,000 miles per year, using fuel prices that represent a national average. This means that if you drive significantly more than 15,000 miles annually, or if fuel prices in your area are higher than the national average, your actual fuel costs will likely exceed the EPA estimate. If you drive less or gas is cheaper, you might spend less. Still, $3,600 is a substantial annual expenditure and an important factor to consider if you’re evaluating the QX80.

Real-world expectations

While the EPA provides a standardized benchmark, real-world fuel economy can vary significantly based on driving habits, terrain, and cargo weight. Aggressive acceleration, frequent braking, and consistently carrying heavy loads will inevitably push fuel consumption beyond the EPA estimates. Owners who frequently tow will see a particularly dramatic drop in MPG. Drivers who adopt a more conservative style, anticipate traffic flow, and avoid unnecessary idling may achieve figures closer to, or even slightly above, the EPA numbers, but consider that an optimistic goal. See QX80 MPG across all years and user-submitted data for more insights.

How it compares

Compared to its competitors, the 2015 Infiniti QX80’s fuel economy paints a familiar picture. A contemporary Cadillac Escalade, with its 6.2L V8, manages around 17 MPG combined in 4WD guise. The Lincoln Navigator, similarly equipped, achieves comparable figures. These large, body-on-frame SUVs occupy a similar niche: offering immense space, towing capacity, and a luxurious experience, but demanding a penalty at the pump. Even shifting to competitors with smaller engines doesn’t always yield massive gains. For instance, a V6-powered Acura MDX or Lexus GX offers better fuel economy, but trades away some of the QX80’s rugged capabilities and sheer size. Anyone interested in fuel numbers for the whole lineup can reference all Infiniti fuel economy data to put the QX80’s MPG in context.

Tips to maximize Efficiency

Tire pressure significantly impacts fuel economy, especially in a heavy vehicle like the QX80. Make sure your tires are inflated to the recommended pressure; you can usually find it on the door jamb or in the owner’s manual. Underinflated tires increase rolling resistance, forcing the engine to work harder and consume more fuel.

Avoid aggressive driving habits. Rapid acceleration and hard braking consume significantly more fuel than gradual and smooth inputs. Anticipate traffic flow and maintain a steady speed whenever possible. The QX80’s powerful V8 is tempting to unleash, but resist the urge if lower fuel costs are important.

Minimize idling. Modern engines consume fuel even when stationary. If you anticipate being stopped for more than a minute, consider turning off the engine. This simple habit can save a surprising amount of fuel over time, particularly in stop-and-go city driving.

Reduce weight whenever possible. The QX80 is already a heavy vehicle, so avoid carrying unnecessary cargo. Remove any items from the cargo area that are not essential, as every extra pound increases the engine’s workload and reduces fuel economy. Also, keep the roof rack clear if you’re not using it, as wind resistance will also play a role.