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 comprising: a lubricating base oil comprising 0.5% to 70% by mass of an ester base oil based on the total amount of the lubricating base oil, and having a kinematic viscosity at 40 C. of 18 to 28 mm.sup.2/s; and an organic molybdenum compound in an amount of 100 to 1000 mass ppm in terms of the molybdenum element based on the total amount of the lubricating oil composition, wherein the lubricating oil composition has a kinematic viscosity at 40 C. of 50 mm.sup.2/s or less.

A method for improving corrosion resistance, while maintaining or improving fuel efficiency, 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 comprising a lubricating oil base stock as a major component, and at least one friction modifier having an elemental composition comprising one or more of nitrogen (N), oxygen (O), and phosphorus (P), as a minor component. The formulated oil has a corrosion factor, based on the elemental composition of the at least one friction modifier, of less than 500, as determined by the formula:

12900(N wt %)+3967(O wt %)8524(P wt %)250=corrosion factor.

The lubricating oils are useful as passenger vehicle engine oils (PVEO) and commercial vehicle engine oils (CVEO).

A lubricating oil composition may contain a base oil (A) and a dispersant-type viscosity index improver (B), in which the nitrogen atom content based on the solid content of the dispersant-type viscosity index improver (B) is 0.50 to 1.50% by mass, and the weight-average molecular weight (Mw) thereof is 100,000 or more, and the content in terms of the solid content based on the total amount of the composition of the dispersant-type viscosity index improver (B) is more than 0.05% by mass and less than 5.0% by mass. The lubricating oil composition may exert excellent wear resistance in a state contaminated with soot.

The present invention relates to additives for reducing friction and wear in lubricants. In particular, the present invention relates to novel salts and their use in lubricating oil compositions for reducing friction and wear. In particular, the present invention relates to one or more ionic liquids, wherein the one or more ionic liquids comprise one or more cations and one or more Group 6 metal mononuclear metallate anions.

Disclosed is a lubricating engine oil composition for use in down-sized boosted engines comprising a lubricating oil base stock as a major component, and at least one silane-containing compound. Also disclosed is a method for preventing or reducing low speed pre-ignition in a direct injected, boosted, spark ignited internal combustion engine, and the use of at least one silane-containing compound in a lubricating engine oil composition for preventing or reducing low speed pre-ignition in a direct injected, boosted, spark ignited internal combustion engine.

Disclosed is a lubricating engine oil composition for a direct injected, boosted, spark ignited internal combustion engine comprising from about 25 to about 3000 ppm of metal from at least one manganese-containing compound, based on the total weight of the lubricating oil. Also disclosed is a method for preventing or reducing low speed pre-ignition in an engine lubricated with said lubricating engine oil composition.

The present disclosure is directed to an additive composition for engine oils comprising; (a) an alkenyl-substituted succinic anhydride and (b) a polyamine compound and (C) Co-additives, wherein the reaction product has a ratio of the amide to imide infrared absorption peak areas of about 1:1.2 to about 1.6. The said reaction product is effective to prevent engine deposits along with protecting elastomeric seal material of an internal combustion engine and also improves piston cleanliness and ring sticking performance of an internal combustion engine.

Provided is a non-Newtonian engine oil lubricant composition with improved fuel efficiency and engine wear protection. The lubricant composition includes a major amount of a base oil including a Group II base stock and an optional Group V base stock, from 0.1 to 9.0 wt. % of at least one viscosity modifier and from 0.1 to 1.2 wt. % of at least one friction modifier. The non-Newtonian engine oil lubricant composition has a kinematic viscosity at 100 deg. C. of less than or equal to 10 cSt and an HTHS (ASTM D4683) of less than or equal to 2.2 cP at 150 C. Also provided are methods of using the lubricant composition in internal combustion engines and methods of making the lubricant composition.

A lubricating oil composition containing a base oil, an organic molybdenum compound, and a metallic detergent, wherein the metallic detergent contains calcium sulfonate, and the content of the calcium sulfonate in terms of calcium atoms is 0.12% by mass or more based on the mass of the composition, the content ratio of molybdenum atoms derived from the organic molybdenum compound to soap groups derived from the metallic detergent based on the lubricating oil composition, [Mo/soap groups], is 0.02 or more at a mass ratio, and the HTHS viscosity at 150? C. is 1.3 mPa.Math.s or more and less than 2.3 mPa.Math.s. The lubricating oil composition has low viscosity and excellent lubricity.