The 2.2-litre turbo-diesel sedan was driven the 4615km from New York to Los Angeles - the equivalent of travelling from London to the Sahara - taking in 11 states, three time zones and eight days.
The British team only stopped to fill up the car four times. Jaguar, which now claims the car as the company's most fuel efficient ever, says the test was "a graphic demonstration of the strength, engineering integrity and efficiency of the car".
Paul Alcock, XF Project Manager, Jaguar Cars - who was in a following vehicle for the trip - says the project was designed primarily to test the potential economy of the XF 2.2.
"The incredible figures achieved by the car were accomplished through making every element of the new XF as efficient as possible - from its aerodynamics to its four-cylinder 2.2-litre diesel engine linked to an eight-speed gearbox," he says.
Driven by independent testers, David and Alexander Madgwick, the XF 2.2 was a stock-standard, UK-registered, right-hand drive vehicle.
In the coast to coast journey the car maintained an average speed of 85km/h and incorporated a range of real-life scenarios - including the busy roads exiting New York and, towards the end of the trip, entering Los Angeles, road works, high winds and a climb to 2240m above sea level.