All-wheel drive

BMW automobiles such as the BMW X5 come with permanent all-wheel drive. Under normal driving conditions, 62 per cent of the engine's drive power is transmitted to the rear wheels while 38 per cent goes to the front.

Rear-wheel drive is provided via the cardan shaft, with the central power divider and an integrated central differential in between. Three features work together to ensure the optimum flow of power to the front wheels: the chain-driven propeller shaft running parallel to the engine, the front axle differential and the drive shaft.

The greatest advantage of all-wheel drive is, of course, that four drive wheels provide substantially better traction under all conditions.