Patent ID: 7651984

Claim:
A lubricant comprising a) a major amount of oil of lubricating viscosity, b) at least one emulsifier, derived from a hydrocarbyl substituted carboxylic acylating agent, the hydrocarbyl portion of said acylating agent having about 50 to 500 carbon atoms, capable of forming a water in oil emulsion, c) from about 2 to about 50 weight percent of an oil insoluble solvent or solvent blend and d) a base comprising magnesium oxide, magnesium hydroxide, magnesium carbonate, calcium hydroxide, or calcium carbonate or combinations thereof, wherein said base contributes at least 1 TBN to said lubricant, at least 10 wt. % of said base is insoluble in the oil insoluble solvent, and said insoluble base is added as a preformed chemical compound rather than being characterized as formed by an in situ chemical reaction within the oil phase of a aluminum, alkali or alkaline earth base with an acid in the presence of an emulsifier (overbasing) and wherein said base is not a borate compound.