1999 Mercury Villager Owner's Manual - Page 196

Maintenance and care 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. Change your engine oil and filter according to the appropriate schedule listed in the Scheduled Maintenance Guide. It is recommended that you replace the engine oil drain plug washer each time the engine oil is changed. Ford production and aftermarket (Motorcraft) oil filters are designed for added engine protection and long life. If a replacement oil filter is used that does not meet Ford material and design specifications, startup engine noises or knock may be experienced. It is recommended you use the appropriate Motorcraft oil filter (or another brand meeting Ford specifications) for your engine application. 196