xDrive: description, features, and operating principle

xDrive: description, features, and operating principle

xDrive is a proprietary all-wheel drive system which has been installed on BMW cars since 2003. For most models it is available as an option or as standard. It improves the vehicle’s off-road capability on slippery surfaces and rough terrain.

How xDrive works

All-wheel drive can be:

  • Full-time: It is based on a RWD layout. Torque is distributed between the axles by a multi-plate friction clutch with electronic control and a servo drive and linkage mechanism are responsible for locking. It is normally partially locked when driving. The torque is distributed between the front and rear axles in a 40:60 ratio. If the rear wheels slip, the clutch is locked further. A higher torque is transferred to the front axle. In case of poor traction of the front wheels, the clutch disengages in order to redistribute the torque to the other axle.
  • On-demand: It is based on a FWD layout. The rear wheels are engaged only if the front ones slip. This is achieved with a Haldex multi-plate clutch.

Popular BMW models equipped with xDrive

AWD typeCars
Full-timeХ1 E84; Х3 E83, F25, G01; X4 F26, G02;Х5 E70, F15, F85, G05; Х6 E71, E72, F16, F86, G06, F96; X7 G07; 7 series E65, E66.
On-demandХ1 F48; X2 F39; 1 series F52, F40; 2 series F44, F45, F46.

Common xDrive malfunctions

MalfunctionsBMW models
Clutch friction plates wear out prematurely due to servo drive failure.7 series E65, E66; Х3 Е83; Х5 Е53, Е70; X6 Е71.
The rear axle final drive often breaks down.Х3 Е83; Х5 Е53, Е70; X6 Е71.
Bearings of the transfer case get damaged due to the friction plates wearing out.Х3 Е83; Х5 Е53, Е70; X6 Е71.

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