The BMW 4-series is available in three different body styles: coupe, convertible and what BMW calls the "Gran Coupe." All three body styles have back seats, but the Gran Coupe actually has a pair of rear doors for easier access to the back seats. Despite the additional doors, the 4-Series Gran Coupe maintains the sloping, swoopy roofline of the 4-Series coupe, giving it a good compromise between coupe styling and sedan practicality. There are two engines available in the 4-Series: 428i models are powered by a 2.0L 4-cylinder turbocharged engine that makes 240 horsepower, while 435i models are powered by a turbocharged 3.0L 6-cylinder engine producing 300 horsepower. Power is sent to the rear wheels via an 8-speed automatic transmission, while a 6-speed manual is a no-cost option on most models. BMW's xDrive all-wheel drive is an option and can be paired with any body style and with any engine, though it does restrict transmission choice to the automatic only. In all, there are four trim levels available with each body style: 428i, 428i xDrive, 435i and 435i xDrive. Optioned correctly, the BMW 428i is able to achieve up to 35 mpg on the highway. The performance-oriented M4 gets a 3.0L twin-turbocharged 6-cylinder. While smaller in displacement than in years past, it is still capable of a very impressive 420 horsepower and 406 lb-feet of torque. M4 models are rear-wheel-drive only and get a choice of a 6-speed manal or a 7-speed dual-clutch gearbox. Trim levels are all similarly equipped across the range, meaning that every 4-Series includes 18-inch alloy wheels, xenon headlights, heated side mirrors with a power folding function, 8-way power adjustable front seats, a wood-trimmed interior, a leather-wrapped steering wheel, 9-speaker sound system, Bluetooth connectivity, a powered glass moonroof, automatic climate control, BMW's iDrive system with a 6.5" color LCD screen, dynamic cruise control and rain-sensing wipers. The M4 comes with a few more standard items, such as touch-screen navigation, Harman/Kardon surround audio and dynamic cruise control. Since the various trims feature similar equipment levels, there are several options and option packages available on the 4-Series. The Cold Weather Package offers heated front and rear seats, a heated steering wheel and retractable headlight washers. A rearview camera and park distance control are included in a Driver Assistance Package, while a blind spot warning system, side and top view cameras and speed limit info are all added should buyers opt for the Driver Assistance Plus Package. An M Sport Package adds different wheels, nicer interior detailing, an upgraded steering wheel, a subtle body kit and sportier bucket seats, while a Dynamic Handling package adds sport suspension and a variable ratio steering rack. A Track Handling Package includes unique wheels, M Sport brakes, adaptive M suspension, and variable sport steering. Finally, a Technology Package includes a navigation system, a heads up display and BMW apps along with real-time traffic updates. The M4 offers as optional, a Driver Assistance Plus package, which includes systems that will warn the driver of lane-departure warning, an imminent forward collision or pedestrians in the road. It also includes a blind-spot detection system with side and top view cameras. The Lighting package includes upgraded LED lighting and automatically dimming high-beams. The Exclusive package includes retractable headlight washers, a heads-up display (HUD), a heated steering wheel, a rear-view camera and rear parking sensors.