See also:

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

Volume
► "Speed volume": speed-dependent volume control. ► "PDC": volume of the PDC signal compared to the entertainment sound output. ► "Gong": volume of ...

Remove attached parts following use
Remove unneeded auxiliary mirrors, roof or rear luggage racks after use. Attached parts on the vehicle impair the aerodynamics and increase the fuel consumption. ...