Oil suppliers are now developing motor oil formulations that will take into account the lubrication demands of '07 diesels. New API (American Petroleum Institute) engine-oil service categories are developed in tandem with new engine, fuel and lubricant technologies.
The most recent diesel categories have been developed mainly to deal with the service requirements of engines redesigned for each successive wave of emission reductions.
Categories and their specifics must be readied early enough so that oil formulators can develop the actual product needed before new engines go on the market. New categories are developed through the cooperation of three industry groups: SAE, ASTM (American Society of Testing Materials) and API.
The latest completed category, CI-4, was introduced in 2002. Work is well under way on PC-10, which is expected to be released as a new category late in 2006. It will be tailored to the needs of engines designed to meet the next official round of emission regs, effective in 2007.
Much of the work that breathes life into each new category is carried out by the ASTM's heavy-duty engine oil classification panel (HDEOCP). This panel, made up of representatives from oil companies, additive suppliers, and engine OEMs, acts on recommendations forwarded by SAE.
From there, HDEOCP defines the tests and limits necessary for an oil to “pass” a new category. At the conclusion of a very exacting process, each new category must be balloted on by no less than four ASTM committees before it is finally approved.