The first licensing of the American Petroleum Institute’s CK-4 and FA-4 heavy duty diesel engine oils – formerly known as PC (proposed category) 11A and B – began on Dec. 1, 2016.
The new categories improve upon existing standards by:
- Providing enhanced protection against oil oxidation.
- Protecting against engine wear, particulate filter blocking and piston deposits.
- Protecting against degradation of low- and high-temperature properties.
These new categories resulted from several years of collaboration between engine manufacturers, oil marketers and additive suppliers, according to officials at American Petroleum Institute (API). The new engine oil standards have also been developed to meet new government regulations and ensure engine oil performance.
API (www.api.org) is the only national trade association that represents all aspects of America’s oil and natural gas industry.
Key Differences
CK-4 engine oils are, basically, a direct replacement for the engine oils now being used and are “backwards compatible” to all current vehicles.
The new FA-4 engine oils, offered in lower viscosity grades, are designed primarily for next-generation engines to help maximize fuel economy without sacrificing engine protection. These oils have limited backwards compatibility.
CK-4 vs CJ-4
CK-4 vs CJ-4 CK-4 vs CJ-4 CK-4 provides improved protection against when compared CJ-4
Oil oxidation Oxidative thickening
Viscosity loss Viscosity loss
AerationParticulate filter plugging Particulate filter blocking
Catalyst poisoning Catalyst poisoning
Engine wear Engine wear
Piston deposits Piston depositsSoot-related viscosity increase Soot handling properties
Degradation of low- and high-temp properties Low- and high-temp stability
FA-4 vs CJ-4
FA-4 vs CJ-4 FA-4 meets CK-4 limits So when compared to CJ-4
Oil oxidation Oxidative thickening
Viscosity loss Viscosity loss
Aeration
Particulate filter plugging Particulate filter blocking
Catalyst poisoning Catalyst poisoning
Engine wear Catalyst poisoning
Piston deposits Piston deposits
Soot-related viscosity increase Soot handling properties
Degradation of low- and high-temp properties Low- and high-temp stability
FA-4 is blended to HTHS (high temperature high shear) viscosity range of 2.9cP‒3.2cP to assist in reducing GHG emissions, and it’s not backward compatible, says API.
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