The sixth generation of BMW's midsize 5 Series luxury sedan debuts for 2010 with an evolutionary rather than a revolutionary design makeover. The front end receives an update, with a wide lower air intake, revised teardrop headlights, reshaped twin kidney grilles, and an overall softer, more fluid tone. Other exterior updates include cleaner, upsweeping lines from front to back and a fastback-style rear end, resulting in a sportier, more coupe-like appearance. The new 5 Series has a wheelbase about 4 inches longer than that of the vehicle it replaces, with longer rear doors and more legroom for rear-seat passengers. For the body structure, BMW makes use of lightweight materials like aluminum and carbon fiber, which provide superior strength and more nimble handling due to the vehicle's lighter weight. Trims for 2010 include the 528i, the 528xi, the 535i, the 535xi, the 535xi Wagon, and the 550i. All trims receive more fuel-efficient versions of current engines, courtesy of the automaker's EfficientDynamics technology, which reduces fuel consumption and CO2 emissions yet ensures dynamic performance. Available engines include inline six-cylinder engines for the 528i/xi and 535i/xi/Wagon, and a 4.8-liter V8 for the 550i. The engines link to either a six-speed manual transmission or a new eight-speed automatic transmission, replacing the previous year's six-speed. Drivers have a choice of a rear-wheel-drive configuation or BMW's xDrive all-wheel-drive system. All-wheel-drive trims receive the "x" designation. The next-generation six-cylinder 5 Series trims ride on 17-inch wheels, while the 550i gets 18-inch wheels. Inside, the BMW 5 Series comes equipped with a number of features common to BMW sedans, including the iDrive turn-and-push vehicle control dial located on the center console, which enables drivers to manage the climate control, audio, navigation, and communications systems. Other features include optional Active Steering, which increases the steering angle at lower speeds, and a head-up display, which beams critical information, such as speed and navigation information, onto the inside of the windshield, so the driver can easily view it. Drivers also can opt to add the same navigation system currently available in the BMW 7 Series, which includes an 80GB hard drive that also services an entertainment server for storing music, photos, maps, and other files.