What is FC-W?

FC-W is the minimum certification standard of the National Marine Manufacturers Association (NMMA) for marine engine oil.  Oils that earn NMMA certification have passed rigorous testing, and have been proven to provide the performance and protection demanded by today's advanced outboard technology.  These oils stand up to extended full-throttle operation, high loads, and the salt and moisture-rich air found in a harsh marine environment.

Automotive engine oil will not pass the rigors of the FC-W test.  Most automotive engines operate below 2500 rpm in cruise conditions, whereas an outboard can typically operate from 4500-6000 rpm all day long.  That kind of stress will shear the molecules of automotive engine oil, drastically reducing the oil's protection.  Simply put, automotive oil is not formulated to provide high-performance protection that FC-W engine oil engineers design into every ounce of marine engine oil.