AMSOIL API diesel oil specifications. The American Petroleum Institute, or API, is the only national trade association that represents all aspects of America’s oil and natural gas industry including production, refinement, distribution and more. API also works with other organizations to set quality and performance standards for engine oils. Two specifications, API CK-4 and API FA-4, established in December 2016 by API, are shaping the next generation of diesel oil performance.
The two specs were developed to support new federal regulations that require diesel engines to be more efficient, have fewer emissions and better fuel economy. As a result of these more demanding requirements, the oil for today’s diesel technology needs to lubricate, dissipate heat and protect the components more effectively and efficiently than ever before. Both new specifications focus on six goals: reduced emissions, improved fuel economy, reduced oxidation, viscosity retention, increased resistance to foam and improved wear protection.
The API CK-4 specification is designed for current model year and older diesel engines and is backward-compatible with API CJ-4 and prior oils. All oil manufacturers will transition from the previous CJ-4 specification to meet the API CK-4 standard. Customers looking for diesel oil meeting API CK-4, CJ-4 or earlier diesel oil specifications should use API CK-4 diesel oil.
AMSOIL offers two product lines that conform to the API CK-4 specification. Customers looking for six times more wear protection should use Signature Series Max Duty Synthetic Diesel Oil. Signature Series is available in 5W-30, 0W-40, 5W-40, and 15W-40 viscosities. For price-sensitive customers looking for four times more wear protection, AMSOIL offers Heavy-Duty Synthetic Diesel Oil. It’s available in 10W-30, 5W-40, and 15W-40 viscosities. The API FA-4 specification includes all the benefits of the CK-4 spec, but is designed to further improve fuel economy and reduce emissions.
AMSOIL has a wide selection of products to give your vehicles and equipment the protection they deserve.
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