2003 Mercury Grand Marquis Owner Guide 4th Printing - Page 201
2003 Mercury Grand Marquis Manual
Page 201 highlights
Maintenance and Specifications Engine oil and filter recommendations Look for this certification trademark. Use SAE 5W-20 engine oil. Only use oils "Certified For Gasoline Engines" by the American Petroleum Institute (API). To protect your engine's warranty use Motorcraft SAE 5W-20 or an equivalent 5W-20 oil meeting Ford specification WSS-M2C153-H. SAE 5W-20 oil provides optimum fuel economy and durability performance meeting all requirements for your vehicle's engine. Do not use supplemental engine oil additives, cleaners or other engine treatments. They are unnecessary and could lead to engine damage that is not covered by Ford warranty. Change your engine oil 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 application. 201 2003 Grand Marquis (grn) Owners Guide (post-2002-fmt) USA English (fus)