Diesel Engine Oil Specifications: Making Sense of CK-4 & FA-4
To meet strict regulations and ensure optimal performance, diesel engine oil must meet certain specifications. The American Petroleum Institute (API) has developed two such specifications: CK-4 and FA-4. These standards are designed to provide superior wear protection and meet the demands of modern diesel engines.
Truckers and diesel enthusiasts invest a significant amount of money in their vehicles, with new semis costing nearly $300,000 and turbodiesel pickups reaching over $90,000 with modifications. While diesel regulations may be a touchy subject, advancements in diesel technology have led to improved engine protection through updated diesel engine oil specifications. These regulations have resulted in better performance and protection for hardworking diesel engines.
2017 model-year diesel technology upgrade
In response to increasingly stringent regulations on fuel efficiency and emissions, diesel technology underwent a significant upgrade in the 2017 model year. These newer engines are constructed with cutting-edge materials, resulting in increased horsepower and torque, higher operating temperatures, and greater boost pressure. Additionally, they can run on up to 20 percent biodiesel. While these advancements are beneficial for diesel owners, they also require diesel oil to meet new demands for engine protection. This is in addition to the ongoing need for increased protection from enthusiasts and professionals alike.
Upgraded protection for older & newer diesels
To keep up with the advancements in diesel engine technology, engine oil must provide better protection than previous generations of oil. This improved performance is necessary for both older diesel vehicles and newer models from 2017 and beyond.
Diesel engine oil specifications (API CK-4 & FA-4) take different paths
The API CK-4 and FA-4 specifications for diesel engine oil have taken different paths to meet the demands of modern diesel engines. With regulations requiring increased fuel economy and reduced emissions, newer diesel engines require a combination of advanced engine technology and unique oil formulations. Some engines can now use oils with lower viscosity, such as 15W-40, to meet these demands while still providing necessary wear protection.
The American Petroleum Institute (API) has set two performance specifications for diesel engine oil: API CK-4 and API FA-4. While both are designed to meet the needs of modern diesel engines, API FA-4 oils are specifically formulated to have a lower viscosity, which can improve fuel efficiency. However, it's important to note that these oils should only be used in diesel engines made in 2017 or later, unless the engine manufacturer recommends otherwise, due to the unique oil technology required to meet these specifications.
While CK-4 is suitable for use in diesel engines from 2017 and older, some engine manufacturers do not allow for the use of FA-4 oils. Therefore, CK-4 is the recommended specification for these engines. It is important to check with the engine manufacturer to determine which specification is appropriate for your diesel engine.
The introduction of two different diesel oil specifications, API CK-4 and FA-4 may seem confusing at first, but they benefit independent trucking companies and contractors by reducing maintenance costs and extending the lifespan of their equipment. This allows them to remain competitive in markets that require maximum reliability and efficiency. To select the appropriate AMSOIL synthetic diesel oil for your specific needs, consult our Product Guide.
