The 3.0L inline 6-cylinder turbocharged engine in the xDrive35i makes 300 horsepower. xDrive50i versions are fitted with an all-aluminum twin-turbo 4.4L V8 with variable valve timing and direct injection. It features what BMW calls a "reverse flow" setup, with its twin turbochargers situated within the valley between the cylinders. It makes 400 horsepower and 450 ft-lb of torque. Powering the xDrive35d is a 265-hp 3.0L inline-6 diesel engine. The Variable TwinPower Turbo engine also produces 425 ft-lb of torque and delivers an EPA estimated 26 mpg on the highway. At the very top of the range is the intense X5 M, featuring 555 horsepower from a tuned version of the xDrive50i's 4.4L V8.
Both the xDrive35i and the xDrive50i use an 8-speed automatic transmission, first introduced in the 5-series Grand Turismo. Brake energy regeneration is also used on both gasoline engines, which uncouples the alternator from the accessory drive system, allowing the battery to only be charged during coasting or braking. This, BMW says, results in up to 2 percent fuel economy boost. The X5 M features a 6-speed automatic as the only transmission option.
Standard safety features include several airbags--driver's and passenger's front and side units as well as head airbags for the first- and second-row seats. In addition, BMW offers Dynamic Stability Control, Dynamic Traction Control, Dynamic Brake Control, Hill Descent Control and Dynamic Cruise Control. Active Cruise Control and Lane Departure Warning systems are also available. There's also a rearview camera that can provide a 360-degree exterior view, a Heads-Up Display that projects onto the windshield in the driver's field of view and a Park Distance Control system that alerts the driver of obstacles behind the vehicle while parking.
The xDrive35i is available in three trim levels, with the base model including automatic xenon adaptive headlamps, rain sensors, HD radio, fog lights, automatic climate control, cruise control, 18-inch wheels and an anti-theft system all as standard equipment. Premium adds 19-inch wheels, iPod integration, tinted glass, leather seats and the availability of a Convenience Package, Active Ventilated Seat Package, Cold Weather Package and Technology Package. The top of the line Sport Activity adds 20-inch wheels, sport seats, performance tires, BMW's Adaptive Drive System and special darkened trim.