The manual will specify:
* The correct viscosity: This is usually something like 5W-20, 5W-30, or 10W-30. The viscosity is crucial for proper lubrication at different temperatures.
* The oil type: This might specify conventional, synthetic blend, or full synthetic oil. Again, the manual will tell you what's best for your engine.
* API Certification: This is an industry standard that indicates the oil meets certain quality requirements. Your manual will list the appropriate API certification.
Using the incorrect oil can severely damage your engine. Don't guess – find your owner's manual! If you can't find it, you can often download a PDF version from the Ford website using your VIN number.