API Engine Oil Classifications For Diesel Engines "C"

API Commercial Engine Service Categories	Related Military or Industry Designations	Diesel Engine Service Description (Year introduced) and API licensing status
CJ-4	None	High-speed, four-stroke engines with advanced emission controls (EGR and diesel particulate filters. (2007) LATEST/CURRENT
CJ-4 Plus*	None	High-speed, four-stroke engines with exhaust gas recirculation (EGR). High soot dispersancy. (2004) CURRENT
CI-4	Mil 2104-H (2004)	High speed, four-stroke engines w/wo EGR emission controls. (2002) CURRENT
CH-4	MIL-L-2104-G (1997)	High speed, four-stroke engines. (1998 emission standards). CURRENT
CG-4	None	Severe duty, high-speed four-stroke diesel engines. (1994) CURRENT
CF	None	Off-road indirect injected engines that use higher sulfur content. Replaced API category CD. (1994) CURRENT
CF-2	MIL-L-2104-F (1992)	Severe duty two-stroke cycle engines needing improved performance. Replaces API category CD-II. (1992) CURRENT
CF-4	None	Typical high-speed, four-stroke cycle engines. (1990) OBSOLETE
CE	None	Severe duty high-speed, four-stroke naturally aspirated and turbocharged engines. (1987) OBSOLETE
CD-II	MIL-L-2104-E (1988) MIL-L-2104-D	Severe duty 2-stroke cycle engines (1987) OBSOLETE
CD	MIL-L-45199B, Series 3 MIL-L-2104C/D/E	Severe duty naturally aspirated and turbocharged engines. (1955) OBSOLETE
CC	MIL-L-2104B MIL-L-46152B	Moderate duty engines. (1961) OBSOLETE
CB	MIL-L-2104A, Supplement 1	Moderate duty engines. (1949-1960) OBSOLETE
CA	MIL-L-2104A	Light duty engines. (1920’s and 1930’s) OBSOLETE