Sulfide- and polysulfide-containing lubricating oil additive compositions and lubricating compositions containing the same

This invention relates to a lubricating composition comprising a major amount of an oil of lubricating viscosity, at least one organic polysulfide comprising less than about 88% dihydrocarbyl trisulfide, from up to about 5% dihydrocarbyl disulfide, and more than about 7 wt. % dihydrocarbyl higher polysulfides, and at least one phosphorus or boron compound, or mixtures of two or more thereof. The invention also relates to concentrates and greases containing the above combination. The invention also relates to methods of making the organic polysulfide.