While this in itself is nothing spectacular, the fact that they averaged a fuel economy of 52.4 mpg over the course of the journey is nothing short of amazing.
The key was the car’s engine. Rather than relying on hybrid technology, the Jaguar XF driven by brothers David and Alexander Madgwick was an XF 2.2 Diesel. This model isn’t currently sold in the U.S. so the brothers, with the help of Jaguar, had one shipped over from the UK.
Jaguar states that the journey was designed primarily to test the potential economy of the XF 2.2 Diesel, however, the fact that it occurred in the U.S. suggests Jaguar's also trying to gauge potential customer interest in the car, which means we may see a diesel option offered on the XF in the U.S. in the not too distant future.
As its name suggests, the XF 2.2 Diesel is powered by a 2.2-liter four-cylinder turbodiesel engine rated at 190 horsepower and 332 pound-feet of torque. The official mileage figure on the European combined cycle is 52.2 mpg, which is rather impressive when you consider the XF is a reasonably sized luxury sedan able to dish off 0-60 times in the eight seconds bracket and top out at 140 mph.
Below is a video montage of David and Alexander Madgwick’s recent U.S. tour in the Jaguar XF 2.2 Diesel.