Mercury 1999 Mountaineer Owner's Manual page 195

4. Open the hood. Protect yourself from engine heat.
5. Locate and carefully remove the engine oil level indicator (dipstick).
4.0L V6 engine
5.0L V8 engine
6. Wipe the indicator clean. Insert the indicator fully, then remove it
again.
If the oil level is between the ADD and FULL marks (4.0L
engine) or between the MIN and MAX marks (5.0L engine), the
oil level is acceptable. DO NOT ADD OIL.
Maintenance and care
ADD 1 QT
MIN MAX
FULL
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