The American Petroleum Institute will introduce a special Service Symbol Donut to help consumers identify the newly-approved FA-4 (PC-11) diesel engine oil.
API approved two new diesel oil standards, FA-4 and CK-4, earlier this year.
The new donut features a shaded section to differentiate API FA-4 diesel oils from CK-4 oils. The API CK-4 Service Symbol Donut will look the same as the current CJ-4 Donut. Most truck manufacturers recommending API-licensed CJ-4 engine oils will likely recommend API CK-4 oils as soon as they are available. API FA-4 oils have been designed to protect diesel engines that are expected to be introduced in 2017. API recommends that technicians and consumers check with the manufacturer of their engine to determine the correct oil to use.
API has put together this website with more information on FA-4 and CK-4 engine oils.