FORD 2004 Explorer v.2 - Manual (Page 232)

Engine Oil Recommendations
4.6L Engine
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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.
4.0L Engine
Look for this certification
trademark.
Use SAE 5W-30 engine oil.
Only use oils “Certified For Gasoline Engines” by the American
Petroleum Institute (API). To protect your engine’s warranty use
2004 Explorer (exp)
Owners Guide (post-2002-fmt)
USA English (fus)
Maintenance and Specifications
232