For the moment, at least, BMW builds the most fuel-efficient luxury crossover on the market today, excluding hybrid models. It’s 2013 X3 xDrive28i, equipped with the 2.0-liter turbocharged four-cylinder engine, will deliver an EPA estimated 21 mpg in the city and 28 mpg on the highway. Compared to last year’s X3 xDrive28i, which used a naturally-aspirated six-cylinder engine, that’s a gain of 2 mpg in the city and 3 mpg on the highway. It also gives BMW bragging rights for the most fuel-efficient luxury crossover, since it now bests the Audi Q5, the Range Rover Evoque and the outgoing Mercedes-Benz GLK in fuel economy. The 2013 X3 xDrive28i will likely beat the new Mercedes-Benz GLK350, too, since the Mercedes is returning with a 3.5-liter V-6 engine. It’s unlikely the BMW will be able to beat the upcoming Mercedes-Benz GLK250 BlueTEC turbodiesel, which will almost certainly take top honors in the fuel economy category. Buyers wanting an X3 with a six-cylinder engine are still in luck, as BMW will again offer the X3 xDrive35i. Don’t expect any fuel economy gains in this model, however, which returns delivering 19 mpg in the city and 26 mpg on the highway. On the plus side, BMW and the EPA are in agreement on the fuel economy of the 2013 X3 xDrive28i. The automaker originally claimed fuel economy of 24 mpg city and 36 mpg highway on its new 328i sedan (which shares an engine with the X3 xDrive28i), until the EPA rated it at 23 mpg city and 33 mpg highway.