xDrive: description, characteristics and principle of operation

xDrive is a proprietary all-wheel drive system that has been used in BMW cars since 2003 equipped. It is available as an option or standard on most models. It optimizes the vehicle's off-road capability on slippery surfaces and rough terrain.

How xDrive works

All-wheel drive can be:

  • Permanent:It is based on a rear-wheel drive layout. By means of a multi-plate friction clutch with electronic control, the torque is distributed to the axles and a servo drive and clutch mechanism are responsible for locking. Normally the clutch is partially locked while driving. The engine's torque is distributed between the front and rear axles in a 40:60 ratio. If the rear wheels slip, the clutch will lock up even more. A higher torque is transmitted to the front axle. If the front wheels lack traction, the clutch disengages so that the torque is transferred to the other axle.
  • Automatic: It is based on a front-wheel drive design. The rear wheels are activated only when the front wheels slip. This is done with the help of a Haldex multi-plate clutch.

Popular BMW models with xDrive

Type of four-wheel drive Cars
Permanent Х1 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
Automatic Х1 F48; X2F39; 1 series F52, F40; 2 series F44, F45, F46

Frequent defects of xDrive

Defects BMW models
The clutch friction plates wear out prematurely due to a defect in the servo drive from. 7 series E65, E66; Х3 Е83; Х5 Е53, Е70; X6 Е71
The final drive of the rear axle often fails. Х3 Е83; Х5 Е53 , Е70; X6 Е71
The transfer case bearings are damaged by worn friction discs. Х3 Е83; Х5 Е53, Е70;  X6 Е71

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