FORD 2009 Explorer Sport Trac v.2 - Manual (Page 325)

WARNING: The fuel system may be under pressure. Remove
fuel filler cap slowly. Otherwise, fuel may spray out and injure
you or others.
WARNING: If you do not use the proper fuel filler cap,
excessive vacuum in the fuel tank may damage the fuel system
or cause the fuel cap to disengage in a collision, which may result in
personal injury.
Choosing the right fuel
Use only 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.
We do not recommend the use of
gasolines labeled as “Regular” in
high altitude areas that are sold with octane ratings less than 87.
87
(R+M)/2 METHOD
2009 07+ Explorer Sport Trac (esp)
Owners Guide, 2nd Printing
USA (fus)
Maintenance and Specifications
325