BMW 5 Series: Remove attached parts 
following use - Saving fuel - Driving tips - BMW 5 Series Owners ManualsBMW 5 Series: Remove attached parts following use

Remove auxiliary mirrors, roof or rear luggage racks which are no longer required following use.

Attached parts on the vehicle impair the aerodynamics and increase the fuel consumption.

    Remove unnecessary cargo
    Additional weight increases fuel consumption. ...

    Close the windows and glass sunroof
    Driving with the glass sunroof and windows open results in increased air resistance and raises fuel consumption. ...

    See also:

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    Door Ajar Light
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    Reporting safety defects
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