| abstract |
(57) Abstract: An engine oil lubricant composition for improving fuel economy when used in an internal combustion engine, comprising an organic phosphorus-containing sulfide and an acylated nitrogen-containing compound. Providing things. A composition comprising a major amount of oil having lubricating viscosity and a fuel improving amount of the following (A) and (B): (A) a compound represented by the following formula: Wherein, in formula (AI), R 1 , R 2 , R 3 and R 4 are independently a hydrocarbyl group, X 1 and X 2 are independently O or S, and n is And (B) an acylated nitrogen-containing compound having a substituent of at least 10 aliphatic carbon atoms. |