Initial availability of the new all-wheel drive powertrain will be limited to the 407-horsepower turbocharged V-8 750i and its long-wheelbase variant, the 750iL. It's not yet clear if other models will get the new xDrive tag as well.
In addition to a new hill descent control feature - a first for an all-wheel drive luxury sedan - the 2010 7-Series will also get a high-tech torque distribution system to maximize grip and performance.
When traveling in a straight line, the gearbox sends 40% of the engine's torque up front, and 60% to the rear, but as the driver turns the wheel, up to 80% of the power can be sent rearward to improve handling and dynamics.
Fuel consumption of the new powertrain is only estimated to be about 1-2mpg greater than the standard sedan. Due for retail sale in late September or early October, the all-wheel drive 750i will likely start about $3,500 above the standard two-wheel drive model.