abstract |
To provide a lubricating oil composition capable of improving lubricating performance in a diesel engine provided with an exhaust gas recirculation (EGR) device. An oil having a large amount of lubricating viscosity, and (i) a copolymer of a monovinyl aromatic hydrocarbon hydrogenated polymer and a conjugated diene polymer, wherein the monovinyl aromatic hydrocarbon hydrogenated polymer portion comprises: A copolymer comprising at least 20% by weight of the copolymer, (ii) an olefin copolymer containing an alkyl or arylamine or amide group, a nitrogen-containing heterocyclic group, or an ester bond, and / or (ii) a dispersing group. A small amount of one or more high molecular weight polymers comprising a derivative of an acrylate or alkyl acrylate copolymer with one or more neutrals selected from phenate / salicylate mixed detergents, sulfur-free phenate detergents and mixtures thereof And / or a small amount of overbased metal-containing detergent. [Selection figure] None |