Provided is a grease composition for a wheel bearing, containing (a) a base oil consisting of a mineral oil and a synthetic hydrocarbon oil, wherein the ratio of the synthetic hydrocarbon oil to the total amount of the mineral oil and the synthetic hydrocarbon oil is 40 to 60 mass %, and the base oil has a kinematic viscosity at 40 C. of 40 to 65 mm.sup.2/s; (b) a thickener of formula (A) wherein R.sup.2 is diphenylmethane, and R.sup.1 and R.sup.3, which may be the same or different from each other, each represent cyclohexyl group or a straight-chain or branched alkyl group having 16 to 20 carbon atoms, with a molar ratio of the cyclohexyl group to the total number of moles of the cyclohexyl group and the alkyl group being 50 to 90 mol %; (c) an amine type antioxidant; and (d) an amine phosphate type antiwear agent. ##STR00001##

A lubricating oil detergent composition comprises an overbased calcium sulfonate and a low ash detergent, which low ash detergent is metal free and comprises the reaction product of an acidic organic compound such as an alkylated salicylic acid, a boron compound and an amine component.

A lubricating oil detergent composition comprises an overbased calcium sulfonate and a low ash detergent, which low ash detergent is metal free and comprises the reaction product of an acidic organic compound such as an alkylated salicylic acid, a boron compound and an amine component.

A metal-containing detergent, suitable for use as a lubricant additive, in the form of a concentrate in oil in which a basic metal-containing material is maintained in dispersion or solution in the oil by a gemini surfactant system comprising, or being derivable or derived from, a double bond-unsaturated carboxylic acid having 8 to 30 carbon atoms, the double bond or bonds of which being functionalized to carry polar groups across or on the double bond or bonds and the carboxylic acid group or groups thereof being functionalized to become an amide or ester group carrying at least one alkyl group having 4 to 20 carbon atoms.

A metal-containing detergent, suitable for use as a lubricant additive, in the form of a concentrate in oil in which a basic metal-containing material is maintained in dispersion or solution in the oil by a gemini surfactant system comprising, or being derivable or derived from, a double bond-unsaturated carboxylic acid having 8 to 30 carbon atoms, the double bond or bonds of which being functionalized to carry polar groups across or on the double bond or bonds and the carboxylic acid group or groups thereof being functionalized to become an amide or ester group carrying at least one alkyl group having 4 to 20 carbon atoms.

The invention is directed to a method for reducing low speed pre-ignition events in a spark-ignited direct injection internal combustion engine by supplying to the sump a lubricant composition which contains an oil of lubricating viscosity and a metal overbased detergent. The metal overbased detergent may be selected from sulfonate detergents, phenate detergents, and salicylate detergents, especially sulfonate detergents with a metal ratio of at least 5.

The invention relates to phosphorous-containing compounds useful as antiwear additive components, lubricant additive compositions and lubricant compositions each comprising such compounds, methods for making and using the same, including methods of lubricating machines and machine parts and methods of extending the useful life of elastomeric seal components of such machines.

A conductive lubricating oil composition including at least one lubricating base oil selected from the group consisting of compounds represented by the following General Formula (1) and compounds represented by the following General Formula (2), and at least one conductivity imparting agent selected from the group consisting of potassium trifluoromethanesulfonate, lithium trifluoromethanesulfonate, lithium nonafluorobutanesulfonate, lithium bis(trifluoromethanesulfonyl)imide, potassium bis(trifluoromethanesulfonyl)imide, and lithium tris(trifluoromethanesulfonyl)methide, in an amount of from 0.01% by mass to 1% by mass, and having a rate of change in conductivity after storage at 120 C. for 200 hours of 10% or less. The definitions of R.sup.1, R.sup.2, m and n in the formulae are as indicated in the specification. Cases of mn=2 are excluded. ##STR00001##

A conductive lubricating oil composition including at least one lubricating base oil selected from the group consisting of compounds represented by the following General Formula (1) and compounds represented by the following General Formula (2), and at least one conductivity imparting agent selected from the group consisting of potassium trifluoromethanesulfonate, lithium trifluoromethanesulfonate, lithium nonafluorobutanesulfonate, lithium bis(trifluoromethanesulfonyl)imide, potassium bis(trifluoromethanesulfonyl)imide, and lithium tris(trifluoromethanesulfonyl)methide, in an amount of from 0.01% by mass to 1% by mass, and having a rate of change in conductivity after storage at 120 C. for 200 hours of 10% or less. The definitions of R.sup.1, R.sup.2, m and n in the formulae are as indicated in the specification. Cases of mn=2 are excluded. ##STR00001##

The present invention provides a lubricating oil composition for two-wheeled vehicles, which is able to not only suppress a lowering of fatigue life of engine parts while making fuel saving properties (in particular, fuel saving properties at the time of low speed) favorable but also make clutch friction characteristics of two-wheeled vehicles favorable. The present invention is concerned with a lubricating oil composition for two-wheeled vehicles, including a base oil (A) having a viscosity index of 120 or more, an ethylene-propylene copolymer (B), and a metal-based detergent (C), wherein the content of the ethylene-propylene copolymer (B) is 0.30% by mass or more on the basis of the whole amount of the lubricating oil composition; the metal-based detergent (C) contains a calcium phenate (C1) and a calcium sulfonate (C2), and a mass ratio of the content (Ca.sub.1) of the calcium phenate (C1) as expressed in terms of a calcium atom to the content (Ca.sub.2) of the calcium sulfonate (C2) as expressed in terms of a calcium atom is satisfied with a relation of (1.0Ca.sub.1/Ca.sub.2); and the lubricating oil composition has a kinematic viscosity at 100 C. is less than 9.3 mm.sup.2/s and an HTHS viscosity at 150 C. is 2.9 mPa.Math.s or more.