Ford 2002 Expedition Owner's Manual page 251

Maintenance and specifications
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete.
CHECKING AND ADDING POWER STEERING FLUID
Check the power steering fluid. Refer to the scheduled maintenance
guide for the service interval schedules. If adding fluid is necessary, use
only Ford Premium Power Steering Fluid.
1. Start the engine and let it run
until it reaches normal operating
temperature (the engine coolant
temperature gauge indicator will be
near the center of the normal area
between H and C).
2. While the engine idles, turn the
steering wheel left and right several
times.
3. Turn the engine off.
4. Check the fluid level in the
reservoir. It should be between the
MIN and MAX lines. Do not add
fluid if the level is in this range.
MAX
MIN
5. If the fluid is low, add fluid in
small amounts, continuously
checking the level until it reaches
the range between the MIN and
MAX lines. Be sure to put the cap
back on the reservoir.
MAX
MIN
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