January 1, 2027, will be the first license date for two new heavy-duty engine oil categories, if all goes as planned.

It’s an advanced, next-generation engine oil standard focusing on ultra-low viscosity oils for modern engines. When purchasing oil, look for the API Service Symbol "Donut" on the label, which is an ...

API PC-12 engine oil categories CL-4 and FB-4 are advancing toward a 2027 launch. Here’s what the changes mean for fleets, ...

The American Petroleum Institute's new diesel engine oil-service categories, API CK-4 and FA-4, will begin appearing in the marketplace on December 1. New API Donuts denoting the categories will ...

API CK-4 and FA-4 diesel engine oils have been available for nearly two years, but with several combinations of categories and viscosities available, it can be difficult to decide which best fits your ...