| abstract |
To improve the performance of a heavy duty diesel (HDD) engine equipped with an exhaust gas recirculation system (ERG) and to provide an engine oil used therefor. An engine comprising an ERG system in which intake air and / or exhaust gas recirculation is cooled below its dew point for a time of at least 10% of the operating time of the HDD engine. The oil lubricated with a lubricating oil composition comprising an oil having a lubricating viscosity and a small amount of one or more polymeric polymers comprising (i), (ii) and / or (iii): Engine: (i) hydrogenated poly (monovinyl aromatic hydrocarbon) segment comprising 20% hydrogenated poly (monovinyl aromatic hydrocarbon) and poly (conjugated diene) copolymer; (ii) alkyl or arylamine, etc. And / or (iii) acrylate or alkyl acrylate copolymer derivatives having a dispersing group. [Selection figure] None |