2011 Ford F450 Super Duty Crew Cab Owner Guide 4th Printing - Page 386

Maintenance and Specifications be void for any damage to the fuel tank or fuel system if the correct genuine Ford or Motorcraft௡ fuel filler cap is not used. WARNING: The fuel system may be under pressure. If the fuel filler cap is venting vapor or if you hear a hissing sound, wait until it stops before completely removing the fuel filler cap. Otherwise, fuel may spray out and injure you or others. WARNING: If you do not use the proper fuel filler cap, excessive pressure or vacuum in the fuel tank may damage the fuel system or cause the fuel cap to disengage in a collision, which may result in possible personal injury. FFV (Flex Fuel Vehicle) fuel cap If your vehicle is FFV capable, it will have a yellow colored fuel cap. Choosing the right fuel If your vehicle is a flexible fuel vehicle (FFV), use only UNLEADED FUEL and FUEL ETHANOL (Ed75-Ed85). If your vehicle is not a flexible fuel vehicle (FFV), then only use UNLEADED fuel or UNLEADED fuel blended with a maximum of 10% ethanol. Do not use fuel ethanol (E85), diesel, methanol, leaded fuel or any other fuel. The use of leaded fuel is prohibited by law and could damage your vehicle. Your vehicle was not designed to use fuel or fuel additives with metallic compounds, including manganese-based additives. Note: Use of any fuel other than those recommended may cause powertrain damage, a loss of vehicle performance, and repairs may not be covered under warranty. Octane recommendations Your vehicle is designed to use "Regular" unleaded gasoline with a pump (R+M)/2 octane rating of 87. Some stations offer fuels posted as "Regular" with an octane rating below 87, particularly in high altitude areas. Fuels with octane levels below 87 are not recommended. 386 2011 F-250/350/450/550 (f23) Owners Guide, 4th Printing USA (fus)