| abstract |
To provide a lubricating oil composition capable of improving lubricating performance in a diesel engine provided with an exhaust gas recirculation (EGR) device. A lubricating oil composition having a sulfur content of less than about 0.3% by weight, wherein the lubricating oil composition is selected from Group I, II, III mineral oils and mixtures thereof. And (i) a copolymer of a monovinyl aromatic hydrocarbon hydrogenated polymer and a conjugated diene polymer, wherein the hydrogenated polymer portion of the monovinyl aromatic hydrocarbon is at least about 20 mass of the copolymer. % Copolymer, (ii) an olefin copolymer containing an alkyl or arylamine or amide group, a nitrogen-containing heterocyclic group, or an ester bond, and / or (iii) an acrylate or alkyl acrylate copolymer having a dispersing group A small amount of one or more high molecular weight polymers including derivatives of coalesced and nitrogen-containing dispersions derived from highly reactive polyisobutylene with a terminal vinylidene content of at least 65% Lubricating oil compositions containing minor amounts of. [Selection figure] None |