Mercury 1996 Sable Manual page 329

Dipstick for power steering fluid (3.0L Vulcan)
6. When you are finished, put the dipstick back
in and make sure that it fits snugly.
3.0L Duratec engine:
4. Check the fluid level in the power steering
fluid reservoir. The fluid level should be
between the MIN and MAX lines on the side
of the reservoir.
5. If the power steering fluid is below the MIN
mark, add fluid in small amounts until the
level is between the MIN and MAX lines on
the side of the reservoir.
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