A lubricating oil composition for an internal combustion engine, the composition including: a lubricating base oil comprising at least one mineral base oil or at least one synthetic base oil or any combination thereof, the lubricating base oil having a kinematic viscosity at 100 C. of 4.0 to 4.5 mm.sup.2/s and a NOACK evaporation loss at 250 C. of no more than 15 mass %; (A) a calcium-containing metallic detergent in an amount of no less than 1000 mass ppm and less than 2000 mass ppm in terms of calcium on the basis of the total mass of the composition; (B) a magnesium-containing metallic detergent in an amount of 100 to 1000 mass ppm in terms of magnesium on the basis of the total mass of the composition; and optionally (C) a viscosity index improver in an amount of less than 1 mass % on the basis of the total mass of the composition.

The lubricating oil composition of the present invention contains, together with a base oil, a viscosity index improver (A) including a comb-shaped polymer (A1), a detergent dispersant (B) including an alkali metal borate (B1) and an organometallic compound (B2) containing a metal atom selected from an alkali metal atom and an alkaline earth metal atom, and a friction modifier (C) including a molybdenum-containing friction modifier, with the total content of an alkali metal atom and an alkaline earth metal atom being 2,000 mass ppm or less. The lubricating oil composition of the present invention has excellent detergency, fuel saving properties, and LSPI-preventing properties.

To provide a friction-reducing agent containing no sulfur nor phosphorus and being excellent in friction-reducing properties, and a lubricating oil composition using it. An alkanolamine represented by the following formula is used as a friction-reducing agent:

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wherein A.sub.1 and A.sub.2 are each independently a hydroxy group or a hydrogen atom, provided that A.sub.1 and A.sub.2 are not hydrogen atoms at the same time, R.sub.1 is a hydrocarbon group having at most 30 carbon atoms, R.sub.2 to R.sub.6 are each independently a hydrogen atom or a hydrocarbon group having at most 30 carbon atoms, and m and n are each independently an integer of from 0 to 10.

Disclosed is a lubricating oil composition which comprises: (a) a major amount of an oil of lubricating viscosity having a kinematic viscosity at 100 C. in a range of about 2 to about 50 mm.sup.2/s, (b) an overbased metal salt of an alkyl-substituted phenate detergent, wherein the alkyl group is derived from an isomerized normal alpha olefin having from about 10 to about 40 carbon atoms per molecule and having an isomerization level (I) of the normal alpha olefin of from about 0.1 to about 0.4 in an amount to provide at least 1000 ppm of calcium, (c) one or more magnesium-containing detergents having about 100 to about 1000 ppm of magnesium, based on the total weight of the lubricating oil composition, and (d) one or more zinc dialkyl dithiophosphate compounds derived from a primary alcohol.

A lubricating composition including an oil of lubricating viscosity and a benzazepine compound. Methods of using such lubricating compositions are also disclosed.

The present disclosure relates to lubricating compositions having a stable viscosity upon oxidization through select amounts and relationships of detergent metals and soap contents.

The disclosed technology provides a lubricating composition comprising an oil of lubricating viscosity and 0.01 wt % to 10 wt % of an oxyalkylated aromatic polyol compound, wherein the aromatic compound has at least one alkoxy group represented by OR.sup.1 group, R.sup.1 is hydroxyalkyl, or a (poly)ether group, and either: at least one hydroxyl group, or at least one alkoxy group represented by OR.sup.1 group, where R.sup.1 is alkyl, or a (poly)ether group, or at least one oxyalkyl group represented by OR.sup.1, where R.sup.1 is hydroxyalkyl or a (poly)ether group. The disclosed technology further relates to a method of lubricating a mechanical device (such as an internal combustion engine) with the lubricating composition. The disclosed technology further relates to the use of the oxyalkylated aromatic polyol compound in the lubricating composition to a passenger car internal combustion engine at least one of (i) control of fuel economy, (ii) control of corrosion, (iii) cleanliness, and (iv) control of bore wear.

A process for producing a borated polyalkenyl succinimide dispersant composition in which the boron is incorporated primarily as cyclic metaboric acid moieties and the equivalents of boron incorporated per equivalent of nitrogen in the succinimide carrier is greater than 2; in which process a slurry of orthoboric acid is added to a polyalkenyl succinimide to form a reaction mixture, which reaction mixture is then heated under conditions (at a temperature and pressure and for a time) sufficient to remove from the reaction mixture from about 0.8 to about 1.2 moles of water of reaction per mole of boric acid charged.

A method for improving oxidation stability and viscosity control, while maintaining or improving cleanliness performance and deposit control, in an engine or other mechanical component lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and a mixture of (i) at least one detergent, and (ii) at least one antioxidant, or a mixture of (i) at least one detergent, (ii) at least one dispersant, and (iii) at least one antioxidant, as minor components. The at least one detergent comprises a sulfonate detergent, the at least one dispersant comprises a borated dispersant, and the at least one antioxidant includes an alkylated diphenylamine. The engine or other mechanical component is lubricated with the lubricating oil operating in the presence of biodiesel fuel. A lubricating oil formulated with the above major and minor components.

The present invention generally relates to lubricating oil compositions useful for vehicles such as industrial machinery, especially transport, construction, and agricultural machinery. Also disclosed is a method for maintaining friction in said vehicles comprising lubricating said vehicles with said lubricating oil compositions.