FORD 2003 F-550 v.1 - Manual (Page 196)

3. Recheck the engine oil level. Make sure the oil level is not above the
MAX mark on the engine oil level indicator (dipstick).
4. Install the indicator and ensure it is fullyseated.
5. Fullyinstall the engine oil filler cap byturning the filler cap clockwise
1/4 of a turn until three clicks are heard or until the cap is fullyseated.
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.
SAE 5W-20 engine oil is recommended.
Onlyuse oils “Certified For Gasoline Engines” bythe American
Petroleum Institute (API). Use Motorcraft or an equivalent 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, oil treatments or engine
treatments. Theyare unnecessaryand could, under certain conditions,
lead to engine damage which is not covered byyour warranty.
Change your engine oil and 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 maybe experienced.
It is recommended you use the appropriate Motorcraft oil filter (or
another brand meeting Ford specifications) for your engine application.
Maintenance and Specifications
196