Ford 2003 Mustang Owner's Manual page 147

Maintenance and care
Adding engine oil
1. Check the engine oil. For instructions, refer to
Checking the engine oil in this chapter.
2. If the engine oil level is not within the normal
range, add only certified engine oil of the
recommended viscosity. Remove the engine oil filler
cap and use a funnel to pour the engine oil into the
opening.
3. Recheck the engine oil level. Make sure the oil
level is not above the F in FULL mark on the engine
oil level indicator (dipstick).
4. Install the indicator and ensure it is fully seated.
5. Fully install the engine oil filler cap by turning the
filler cap clockwise until three clicks can be heard.
To avoid possible oil loss, DO NOT operate the
vehicle with the engine oil level indicator
and/or the engine oil filler cap removed.
Engine oil and filter recommendations
Look for this
Certification
Trademark.
Use SAE 5W-30 motor oil certified for gasoline
engines by the American Petroleum Institute (API).
Motor oil displaying the API Certification Trademark
will meet all requirements for your vehicle's engine.
Ford oil specification is WSS-M2C153-G.
Do not use supplemental engine oil additives, oil
treatments or engine treatments. They are
unnecessary and could, under certain conditions,
lead to engine damage which is not covered by your
warranty.
147