Lincoln 1997 Continental Owner's Manual page 229

It may be necessary to add some oil between oil
changes. Make sure you use a CERTIFIED engine
oil of the preferred viscosity. Your vehicle's
warranty coverage may not apply if engine damage
is caused by the use of improper engine oil.
Add engine oil through the oil filler cap highlighted
in yellow. To add oil, remove the filler cap and use
a funnel to pour oil into the opening. Be careful not
to overfill the engine. Recheck the oil level after 30
minutes to allow the oil to settle.
Changing the Engine Oil and the Oil
Filter
Change your engine oil and oil filter according to
these mileage and time requirements, whichever
occurs first.
228
Refer to the Maintenance Schedule booklet for
additional information.