Oil category will help engine manufacturers meet tightening NOx limits applied to Model Year 2027 equipment and beyond. The API is expected to dub the oils CL-4 and FB-4 when they hit store shelves on Jan. 1, 2027. Oil must pass common performance tests and limits, but the thinner FA-4 is needed to help manufacturers meet tighter limits on greenhouse gas emissions. Karin Haumann, Shell's OEM technical services manager, chairwoman of API's new category development team. Engine manufacturer Haumann: "Oils will look more different now than I think they did in the transition from CJ-4 to CK-4" Haumann says.
Proposed Category 12 will likely "diverge" even further, she says. New tests for oils with OW-20 and 5W-20 weights will help to "future-proof" the category for engine manufactures, she adds. Haumann: "We're adding a test that doesn't exist now, and we're also limiting the amount of one of the anti-wear components that we're able to utilize" at the same time. Two traditional tests are being phased out because the related engine parts are too hard to come by. Granted, several of today's oils already meet that manufacturer-specific requirement.
Haumann: "You don't have to worry about things like shear stability or soot control or those things because we have those minimum standards". And the steps to resist oxidation offset rising engine temperatures that would otherwise thicken the oil.
Even when the work is done, API has a mandatory year-long waiting period to ensure that all oil manufacturers and marketers have the time to access the same tests.