Next generation, API-certified diesel engine oils officially debut

Sources: American Petroleum Institute, Washington, D.C.; CP staff

Lubricant producers can begin marketing two new American Petroleum Institute-licensed categories, CK-4 and FA-4. Soon to be referenced in on- and off-road diesel engine manufacturer specifications, they exhibit improved shear stability, oxidation resistance and aeration control properties against the API CJ-4 formulations they succeed. The API Lubricants Group developed the categories’ performance thresholds and testing guidelines to a) meet the varying needs of aging, new and in-service power packages; and, b) help on- and off-road engine manufacturers address more stringent regulations.

“December 1 is an industry milestone as it marks the first day CK-4 and FA-4 engine oils can be marketed and sold on retail shelves or in bulk,” said API Engine Oil Licensing and Certification System Senior Manager Kevin Ferrick. “The time between approval of the categories last winter and the first licensing gave large, medium, and small oil marketers the ability to test their new formulations and ready them for market. This signals the culmination of almost nine years of cross-industry collaboration in the development of the new standards.”

CK-4 oils replace API CJ-4 products and are backward compatible with most applications where engine manufacturers recommend the latter. API FA-4 oils are formulated to provide protection in some current and new on-road engines, and augment compliance with anticipated emissions control and fuel economy rules covering such power. They have limited or no backward compatibility with on- and off-road diesel engines for which manufacturers recommend CJ-4 lubricants.

Both CK-4 and FA-4 best existing standards by providing enhanced protection against oil oxidation and engine wear, particulate filter blocking, piston deposits, and degradation of low- and high-temperature properties. Technicians and consumers need to check owner’s manuals or with engine manufacturers to determine which new oil is right for their vehicle, API notes. Visually different API Service Symbol Donuts distinguish the two categories: the FA-4 Donut features a shaded section, the CK-4 Donut maintains the CJ-4 scheme. Joining the API Lubricants Group in developing the categories were the American Chemistry Council and Truck & Engine Manufacturers Association. —

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