2003 Mercury Mountaineer Owner Guide 3rd Printing - Page 216
2003 Mercury Mountaineer Manual
Page 216 highlights
Maintenance and Specifications 4.0L Engine Look for this certification trademark. SAE 5W-30 engine oil is recommended. Only use oils "Certified For Gasoline Engines" by the American Petroleum Institute (API). Use Motorcraft or an equivalent oil meeting Ford Specification WSS-M2C205-A. 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 according to the appropriate schedule listed in the scheduled maintenance guide. Engine Oil Filter Recommendation Change your engine oil filter according to the appropriate schedule listed in the scheduled maintenance guide. 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, start-up 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. 216