| 摘要 |
Engine oil compositions are provided containing (A) a lubricating base oil having a kinematic viscosity at 100° C. of 3 to 6 mm2/S, a viscosity index of 120 or more, and a total aromatic content of 5 percent by mass or less and (B) a polymethacrylate-based viscosity index improver, preferably having a weight average molecular weight of 180,000 or more, (A) and (B) being blended in such an amount that the composition has a kinematic viscosity at 100° C. of 4.0 to 9.3 mm2/s. The engine oil compositions may also contain a molybdenumdithiocarbamate, as well as one or more other engine oil additives. The engine oil compositions preferably have a high temperature, high shear viscosity at 150° C. of 2.4 to 2.7 mPa.s, a NOACK evaporation loss of 16 percent by mass or less, and a CCS viscosity at -25° C. of 3500 mPa.s or less.
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