FORD 2009 E-450 v.1 - Manual (Page 286)

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.
Cleaner air
Ford endorses the use of reformulated “cleaner-burning” gasolines to
improve air quality, per the recommendations in the Choosing the right
fuel section.
Octane recommendations
Do not be concerned if your engine
sometimes knocks lightly. However,
if it knocks heavily under most
driving conditions while you are
using fuel with the recommended
octane rating, see your authorized dealer to prevent any engine damage.
Unleaded Gasoline Engines
Your vehicle is designed to use “Regular” unleaded gasoline with a pump
(R+M)/2 octane rating of 87. We do not recommend the use of gasolines
labeled as “Regular” in high altitude areas that are sold with octane
ratings less than 87.
FFV engine
Your vehicle is designed to use Fuel Ethanol (Ed75–Ed85),“Regular”
unleaded gasoline or any mixture of the two fuels.
Use of other fuels such as Fuel Methanol may cause powertrain
damage, a loss of vehicle performance, and your warranty may be
invalidated.
87
(R+M)/2 METHOD
2009 Econoline (eco)
Owners Guide, 1st Printing
USA (fus)
Maintenance and Specifications
286