2005 Mercedes G-Class Owner's Manual - Page 236

Operation At the gas station ! The fuel filler cap is tethered to the fuel filler neck. Do not drop the cap. It could damage the vehicle paint finish. When refueling the vehicle, make certain that no gasoline comes into contact with plastic tail lamp to prevent damaging the lens. i Leaving the engine running and the fuel cap open can cause the ? malfunction indicator lamp (USA only) or the ± malfunction indicator lamp (Canada only) to illuminate. See also "Practical hints" section ( page 292). Check regularly and before a long trip i Use only premium unleaded gasoline with a minimum Posted Octane Rating of 91 (average of 96 RON/86 MON). Information on gasoline quality can normally be found on the fuel pump. More information on gasoline can be found in the Factory Approved Service Products pamphlet. G 500 1 Coolant 2 Brake fluid 236