Development for a new diesel engine oil category has commenced! Last spring, the Truck and Engine Manufacturers Association requested a new category because of the anticipated engine technology advancements. PC-12, the name of the new diesel engine oil category, will supersede the existing API CK-4 and API FA-4 categories.

PC-12 is scheduled for a first licensing date no later than January 1, 2027. The first licensing date of PC-12 coincides with the anticipated implementation date for the U.S. Environmental Protection Agency (EPA) and California Air Resources Board (CARB) heavy-duty on-highway regulations.

Users can expect PC-12 to have an increase in oxidation performance compared to API CK-4 and API FA-4 categories, as well as new wear test capability. PC-12 will feature improved after-treatment capability concerning chemical limits and the expansion of elastomer compatibility in both subcategories.

The Diesel Engine Oil Advisory Panel has already announced backward compatibility will be maintained in the C subcategory. Like previous new categories, the new F subcategory will replace FA-4 and lower viscosities will be added to the F subcategory.

As mandates from the government continue to be executed, the need for new classifications of lubricants continues to arise. When considering switching the viscosity or type of your engine oil, we recommend consulting your lubricant expert for assistance with a transition plan. U.S. Lubricants has a team of experts and product engineers that can offer guidance for a smooth transition to help you find a better way.

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