In the SUV segment, luxury or not, consumers demand one thing: more space. That's why the 2018 X3’s wheelbase is now 54 mm longer, offering occupants a little more room. Besides the xDrive30i and its 248-horsepower four-cylinder turbo, a 355-horsepower M40i version has been added. The X4 remains unchanged for the 2018 model year, offering the same drivetrains as the X3.