Ford 1998 Windstar Owner's Manual page 333

Use of leaded fuel in your vehicle without a proper conversion
may damage the effectiveness of your emissions control system
and may cause engine knocking or serious engine damage. Ford
Motor Company is not responsible for any damage that is
caused by use of improper fuel.
You may also have difficulty importing your vehicle back into
the U.S. if you use leaded fuel.
If your vehicle must be serviced while you are traveling or
living in Central or South America, the Caribbean, or the
Middle East, contact the nearest Ford dealership. If the
dealership cannot help you, contact:
If you are in other foreign countries, contact the nearest Ford
dealership. If the dealership cannot help you, they can direct
you to the appropriate Ford affiliate office.
If you buy your vehicle in North America and then relocate
outside of the U.S. or Canada, register your Vehicle
Identification Number and new address with Ford Motor
Company Export Operations.
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