The American Petroleum Institute said it has so far issued 525 licenses for API CK-4 and 76 licenses for API FA-4. API CJ-4, the previous heavy-duty diesel engine oil category, had just under 1,000 licensees at its peak.
Kevin Ferrick, senior manager of API’s Engine Oil Licensing and Certification System (EOLCS), said this is a “good number since we have only been licensing since December.”
On December 1, 2016, API CK-4 and API FA-4 products began appearing on store shelves, to help diesel engine manufacturers meet more stringent emissions requirements, particularly in the United States.
API CK-4 and FA-4 oils are designed for different applications. API CK-4 oils replaced API CJ-4 engine oils and are backward compatible with most applications where engine manufacturers recommend API CJ-4. CK-4 oils provide a number of improvements over API CJ-4, including improved shear stability, oxidation resistance and aeration control.
API FA-4 oils provide similar improvements over API CJ-4 oils, but API FA-4 oils are only intended for use in newer on-highway diesel engines. API FA-4 oils have limited or no backward compatibility with on and off-highway diesel engines where engine manufacturers recommended API CJ-4.
API developed two visually different API Service Symbol Donuts so that consumers can easily distinguish between the two categories. The new API FA-4 Donut features a shaded section to differentiate API FA-4 oils from CK-4 oils. The API CK-4 Donut look the same as the current CJ-4 Donut.
These new oil standards were developed to better protect new and older engines, improve engine oil performance, and help engine manufacturers meet 2017 U.S. federal government emissions standards. CK-4 and FA-4 improve upon 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.
The new categories are the result of several years of collaboration between engine manufacturers, API’s Lubricants Group, the Truck & Engine Manufacturers Association (EMA), ASTM International and the American Chemistry Council (ACC).