FORD 1998 Expedition - Manual (Page 155)

If the engine coolant has not been checked at the recommended interval,
the engine coolant reservoir may become empty. If this occurs, add
engine coolant to the reservoir. For more information on engine coolant
maintenance, refer to Adding engine coolant in this chapter.
Automotive fluids are not interchangeable; do not use engine coolant,
antifreeze or windshield washer fluid outside of its specified function and
vehicle location.
Adding engine coolant
Do not put engine coolant in the reservoir for the windshield
washer fluid.
Do not mix conventional green coolant, orange coolant or
recycled coolants together in your vehicle. Use only the type of
coolant with which your vehicle was originally equipped. If you
are unsure which type of coolant your vehicle requires, contact
your local dealer.
If sprayed on the windshield, engine coolant could make it difficult to see
through the windshield.
When the engine is cool, add a 50/50 mixture of engine coolant and
water to the engine coolant reservoir.
Plain water may be added in an emergency, but you MUST replace it
with a 50/50 mixture of coolant and distilled water as soon as possible.
Check the coolant level in the coolant reservoir the next few times you
drive the vehicle. If necessary, add enough of a 50/50 mixture of coolant
and water to bring the liquid level into the cold fill range on the
reservoir.
Never remove the coolant reservoir cap while the engine is
running or hot.
If you must remove the coolant reservoir cap, follow these steps to avoid
personal injury:
1. Before you remove the cap, turn the engine off and let it cool.
2. When the engine is cool, wrap a thick cloth around the cap. Slowly
turn cap counterclockwise until pressure begins to release.
3. Step back while the pressure releases.
Maintenance and care
155