When the American Petroleum Institute announced that it had approved its latest diesel engine oil standards API Service Categories CK-4 and FA-4, it marked a significant milestone in the development of diesel engine oils. API had developed two new standards, rather than one, to meet new emissions and fuel efficiency regulations and provide improved protection for current and future diesel engines.
These new service categories, which become effective December 1, improve upon existing API standards by providing enhanced protection against oil oxidation and protection against engine wear, particulate filter blocking, piston deposits, and degradation of low- and high-temperature properties.
Why new engine oil specifications are needed for heavy-duty diesel engines
Diesel engines have changed significantly since API introduced its last diesel engine oil specification, CJ-4, in 2006. Today’s engines run more efficiently, generate more power and feature different hardware. For example, many use high pressure, common-rail injection systems to improve combustion efficiency; advanced turbocharger technology to increase power output; and diesel particulate filters and selective catalytic reduction to decrease or prevent emissions of harmful oxides of nitrogen and particulate matter.
New emissions regulations
New Environmental Protection Agency and National Highway Traffic Safety Administration emission legislation for diesel-powered commercial transport vehicles, that takes effect in 2017, require significant improvements in fuel consumption that will help to reduce carbon dioxide emissions. The fuel consumption improvements cover different vehicle classes, types and sizes, and specific improvements are required for medium and heavy-duty engines.
Changes in engine technology require changes in oil performance. Oils now have to lubricate ever more effectively, while also cooling, cleaning and protecting these new engine designs effectively. Lower viscosity oils, such as 10W-30, are expected to be one tool used to help deliver fuel economy savings while still providing the protection and durability needed. The new generation of high-performing CK-4 and FA-4 diesel engine oils will provide engine manufacturers with the protection they need as they design cleaner, more fuel-efficient diesel engines.
Lower viscosity oils help improve fuel economy
Lower viscosity oils are known to help increase fuel efficiency, which in turn helps to reduce greenhouse gas emissions. According to the recently published Fuel Efficiency Confidence Report, Class 8 over-the-road fleets can realistically expect fuel savings in the range of 0.5 percent to 1.5 percent by switching from 15W-40 to 5W- and 10W-30 CJ-4 or CK-4 engine oil. The savings from switching to the fuel-efficient FA-4 oil, available December 2016, can be expected to add a further 0.4 to 0.7 percent of increased fuel efficiency.
Increases in fuel economy can result in significant reductions in fuel consumption and carbon dioxide emissions. The reduction in CO2 output arises from the engine running more efficiently and consequently putting less CO2 into the environment.
Selecting the proper oil for your engine
Most truck manufacturers recommending API-licensed CJ-4 engine oils will likely recommend API CK-4 oils as soon as they are available to better protect today’s diesel engines. In contrast, API FA-4 oils have been designed to protect diesel engines that are expected to be introduced in the 2017 model year. API recommends that technicians and consumers check with the manufacturer of their engine to determine the correct oil to use.
API CK-4 and FA-4 will first appear in the API Service Symbol “Donut” December 1. This lead time allows marketers time to test their new formulations and ready them for market. Also, this allows end-users such as fleets and owner-operators to prepare their transition plan after investigating whether their engines need CK-4 and/or FA-4 oils. Here are broad guidelines for the CK-4/FA-4 selection:
Most truck manufacturers recommending API-licensed CJ-4 engine oils will likely recommend truck owners start using licensed API CK-4 oils as soon as they are available. API CK-4 oils will provide enhanced protection for today’s diesel engines.
API FA-4 oils, however, are different. The FA-4 standard describes certain lower viscosity oils specifically formulated for use in select high-speed, four-stroke cycle diesel engines designed to meet 2017 model year on-highway greenhouse gas emission standards. Some engine manufacturers might recommend API FA-4 oils for their previous model-year vehicles, but it is more likely that manufacturers will recommend the oils starting with the 2017 model year engines.
Visit www.NewDieselOil.com for more information about the new API CK-4 and FA-4 service categories.
Source: American Petroleum Institute, by Kevin Ferrick, senior manager for engine oil licensing