See also:

Capacities
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Automatic deactivation during forward travel
The system switches off when a certain driving distance or speed is exceeded. Switch the system back on if necessary. ...

BMW X5 xDrive50i: BMW's Twin-Turbocharged V-8.
The new BMW X5 xDrive50i takes its place as the flagship of the X5 family, yielding 400 horsepower at 5,500 rpm and 450 lb-ft of torque at 1,750 - 4,500 rpm from its twin-turbocharged 4.4 liter V- ...