OEM/Lube News has been advised by Ford Motor Corporation that the company does not recommend the use of API CK-4 nor FA-4 oils in any of their diesel engines.

Starting December 1, 2016 the American Petroleum Institute (API) will begin licensing two new diesel motor categories CK-4 and FA-4. API CK-4 is being released to replace CJ-4. FA-4 is a low viscosity diesel oil released for diesel engines designed for a lower viscosity oil.

Ford Motor says that, due to its low viscosity, API FA-4 oils should not be used in any Ford diesel vehicles at this time.

A Ford Motor Company spokesperson told OEM/Lube News "Motorcraft/Ford Motor Company does not have an engine that uses now or in the near future will use FA-4. Therefore Motorcraft has no oil or plans for an oil that meets FA-4."

Regarding API CK-4, Ford will not be recommending the use of CK-4 motor oils in any Ford diesel engines, new or old. Testing Ford has done on some CK-4 formulations have shown inadequate wear protection compared to CJ-4 formulations developed and licensed before 2016.

Like many other diesel engine manufacturers, with their own internal OEM specification, Ford will now be recommending oils that meet an OEM specification, Ford Material Engineering Specification WSS-M2C171-F1, such as Motorcraft Super Duty Motor oil. The customer should use an oil showing that it meets this specification.

An oil showing CJ-4 in the API donut without showing CK-4 would be acceptable for service even if not showing WSS-M2C171-F1. This oil would most likely be an older CJ-4 formulation, developed and licensed prior to 2016. Field experience and Ford testing has shown that these older CJ-4 formulations provide acceptable 6.7L engine protection.