18 MPG combined isn’t going to win any lower fuel costs awards, but it’s the price of admission for those wanting the distinct driving experience and aesthetic of the 2017 Jaguar XJ 5.0L V8. This isn’t a car for hypermilers, but rather for individuals who value handcrafted luxury and effortless power over outright efficiency. The XJ buyer prioritizes exclusivity, a cossetting interior, and the roar of a supercharged V8, fuel economy takes a backseat to these more visceral qualities.

City and highway performance

Those 18 combined MPG break down into 15 MPG in the city and 23 MPG on the highway, according to the EPA. The city figure reflects the engine’s thirst when navigating stop-and-go traffic, while the highway number demonstrates its ability to cruise relatively efficiently once up to speed. The eight-speed automatic transmission helps in this regard, keeping the engine in its sweet spot for power delivery without constantly revving unnecessarily. Expect that 23 MPG figure to drop if you’re driving at higher speeds or encountering hilly terrain, as the XJ’s weight and aerodynamic profile will start to work against it.

Annual fuel cost

The EPA estimates the annual fuel cost for the 2017 Jaguar XJ 5.0L V8 at exactly $3,200. This calculation is based on driving 15,000 miles per year and using national average fuel prices. Your actual fuel costs will vary depending on your driving habits, the type of roads you typically travel, and the prevailing fuel prices in your area. Drivers who frequently engage in spirited driving or spend more time in congested city environments can expect to exceed this estimate. Those with gentler driving styles and predominantly highway commutes may see slightly lower costs.

Real-world expectations

While the EPA estimates provide a benchmark, real-world fuel economy often differs. Driving style is a significant factor, with aggressive acceleration and hard braking significantly impacting fuel consumption. The condition of the vehicle also plays a role; properly inflated tires, regular maintenance, and avoiding unnecessary weight in the trunk can all contribute to improved fuel efficiency. Wind resistance is also a factor, especially at higher speeds, the brick-like aerodynamics of some SUVs and trucks demand a lot of extra fuel to overcome.

How it compares

The 2017 XJ’s fuel economy is a mixed bag when compared to its competitors. A similarly equipped Mercedes-Benz S550 from the same year achieves a slightly better 20 MPG combined. However, to get a 20 MPG combined in the S-Class, you have to opt for the more pedestrian V6 engine. If you want to match the XJ’s power with a V8 in the S-Class, you’ll sacrifice even more MPG. The BMW 750i, another V8-powered rival, lands in a similar ballpark to the XJ with 17 MPG combined. A Lexus LS 460, known for its reliability, manages a respectable 19 MPG combined, thanks to its naturally aspirated V8, but it lacks the XJ’s supercharged punch. For buyers considering XJ MPG across all years, it’s clear that the pursuit of performance comes at a certain fuel cost. Luxury sedan shoppers are often willing to accept all Jaguar fuel economy data for a badge with prestige and a finely crafted interior.

Tips to maximize efficiency

The XJ’s supercharged V8 rewards a smooth and progressive throttle input. Avoid sudden acceleration and hard braking, as these habits consume more fuel than gradual adjustments. Anticipate traffic flow and maintain a steady speed whenever possible.

Ensure your tires are properly inflated to the recommended pressure. Underinflated tires increase rolling resistance, forcing the engine to work harder and decreasing fuel economy. Check your tire pressure regularly, especially during temperature changes.

Reduce unnecessary weight. Remove any items from the trunk that you don’t need, as added weight increases fuel consumption. Every extra 100 pounds reduces a car’s fuel economy by about 1 percent.

Consider using the XJ’s “Eco” driving mode (if equipped). This mode adjusts the engine and transmission settings to prioritize fuel efficiency, which helps dial back the supercharged engine’s enthusiasm. This is particularly useful for city driving or long highway stretches.

Keep up with regular maintenance. A well-maintained engine operates more efficiently. Ensure that your XJ receives regular oil changes, air filter replacements, spark plug inspections, and other maintenance services as recommended by Jaguar.