Lubricant and additive formulation
An engine lubricant formulated as a complete crankcase motor oil or additive concentrate composed of a combination of chemical constituents including a base oil selected from a synthetic oil, a mineral oil or semi-synthetic base oil (hydrogenated oil) or combination thereof, an oil soluble molybdenum additive, a dispersant inhibitor containing zinc dithiophosphate, and viscosity index improvers and one or more seal swelling agents to lubricate the engine and recondition the seals of new and/or high mileage engines. Addition of a polyalphaolefin and/or one or more esters such as a diester or polyolester may also be utilized therein. The lubricant may be formulated as a complete engine oil crankcase lubricant, or concentrated into an additive for addition to conventional mineral oil based engine oil, synthetic engine oils, or blends thereof in an effective amount of up to 30 percent volume percent, typically from 20 to 25 percent by volume.
1 . An engine crankcase lubricant, comprising:
a base oil selected from the group consisting of Group I solvent refined mineral oils, Group II hydrocracked mineral oils, Group III severely hydrocracked oils or combinations thereof in an amount of up to 90 volume percent;
a synthetic base oil selected from Group IV synthetic polyolefins, Group V synthetic oils comprising esters and napthenes, or combinations thereof in an amount of up to 95 volume percent;
a dispersant inhibitor in an amount of from 0.5 to 35.0 volume percent;
a seal swelling agent selected from the group consisting of substituted sulfolane, phthalate plasticizer, dinonly phthalate plasticizer, dihexylpthalate plasticizer, sulfolanes, phenates, and combinations thereof in an amount of from 0.03 to 1.0 volume percent;
a molybdate compound selected from the group consisting of an oil soluble organo molybdenum, a sulfonated oxymolybdenum dialkydithiophosphate, a molybdenum dithiocarbamate, a molybdenum octoate, a molybdenum sulfide, and a molybdenum oxide in an amount of from between 0.05 to 10.0 volume percent;
a viscosity improver selected from the group consisting of a polyisobutene, a polymethacrylate acid esters, a diene polymer, a polyolefin, a multifunctional viscosity diene polymer, a polyolefin and multifunctional viscosity improver, a styrene-butadiene rubber in mineral oil, a styrene isoprene viscosity improver, and combinations thereof in an amount of from 0.005 to 10.0 volume percent;
a corrosion inhibitor selected from the group consisting of a borate ester, a dimercapto, a thiadiazole, a benzotriazole, a triazole and combinations thereof in an amount of from 0.01 to 10.0 volume percent; and
a pour point depressant selected from the group consisting of a polymethacrylate, an alkylated bicyclic aromatic, a styrene ester, a polyfumerate, an oligomerized alkyl phenol, a dialky ester of phthalate acid, an ethylene vinyl acetate copolymer, and other mixed hydrocarbon polymers in an amount of 0.01 to 5.0 volume percent.