Lubricating compositions for internal combustion engines

摘要

The lubricating oil of the present invention comprises a base oil composed of a mineral and/or synthetic oil which is treated with (A) calcium salicylate overbased with calcium carbonate and having a total base number within specified limits with specified contents (as calcium) and (B) boron-containing succinimide having a specified weight-average molecular weight or less at 0.04wt% or less (as boron derived from the boron-containing succinimide) and/or succinimide having a specified weight-average molecular weight or less at 0.01 to 0.25wt% (as nitrogen), the above percentages being based on the whole composition, and exhibits excellent properties with respect to agglomerating solid impurity particles it contains to a sufficiently large size so as to be captured and removed by an oil filter.