FORD 2006 Freestar v.2 - Manual (Page 293)

If you must replace the fuel filler cap, replace it with a fuel filler
cap that is designed for your vehicle. The customer warranty may
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.
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.
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.
Choosing the right fuel
Use only UNLEADED 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. Studies indicate that
these additives can cause your vehicle’s emission control system to
deteriorate more rapidly. In Canada, premium grade fuel generally
contains more metallic additives than regular grade fuel. We recommend
using regular grade fuel. In Canada, many fuels contain metallic
additives, but fuels free of such additives may be available; check with
your local fuel dealer.
Do not use fuel containing methanol. It can damage critical fuel system
components.
Repairs to correct the effects of using a fuel for which your vehicle was
not designed may not be covered by your warranty.
2006 Freestar (win)
Owners Guide (post-2002-fmt)
USA (fus)
Maintenance and Specifications
293