A lubricating composition including: a base oil, a lubricant additive composition including, as a component (A), an organic molybdenum compound of the formula (1) described in the specification, and as a component (B), an amine compound of the formula (2) described in the specification, and a specific metal-based cleaner, wherein a content of the component (B) is 2.9 to 18.6 parts by mass relative to 100 parts by mass of molybdenum atoms of the component (A), and a content of the metal-based cleaner is 0.1% to 10% by mass relative to a total amount of the lubricating composition, wherein the lubricating composition does not include tetraalkyl thiuram disulphide, and wherein the component (A) in terms of the amount of molybdenum atoms is 400 to 1200 ppm by mass relative to a total amount of the lubricating composition.

A lubricating composition including: a base oil, a lubricant additive composition including, as a component (A), an organic molybdenum compound of the formula (1) described in the specification, and as a component (B), an amine compound of the formula (2) described in the specification, and a specific metal-based cleaner, wherein a content of the component (B) is 2.9 to 18.6 parts by mass relative to 100 parts by mass of molybdenum atoms of the component (A), and a content of the metal-based cleaner is 0.1% to 10% by mass relative to a total amount of the lubricating composition, wherein the lubricating composition does not include tetraalkyl thiuram disulphide, and wherein the component (A) in terms of the amount of molybdenum atoms is 400 to 1200 ppm by mass relative to a total amount of the lubricating composition.

Provided is a lubricating oil composition having a HTHS viscosity at 150° C. in a range of about 1.7 to about 3.2 mPa s and a low temperature cold cranking viscosity of less than 7,000 mPa s at −20° C., comprising: (a) a major amount of an oil of lubricating viscosity having a kinematic viscosity at 100° C. of from 3.5 mm.sup.2/s to 20 mm.sup.2/s and a viscosity index of greater than 120 with a sulfur content of less than 0.03 wt. %, are classified into the API group III, IV, or V base stock category, and have an aromatics content (C.sub.A) of less than 5%; (b) an organomolybdenum compound; (c) a dispersed hydrated alkali metal borate compound; (e) one or more dispersants; (f) one or more calcium-based metal detergents; and (g) optionally, one or more magnesium-based metal detergents. Also provided is a method for improving wear, high temperature detergency, and thermal stability in an engine comprising operating said engine with said lubricating oil composition.

The present invention relates to a lubricating oil composition containing a base oil (A), a molybdenum dithiocarbamate (B), an ester-based ashless friction modifier (C), and a metal salicylate (D), wherein the content of a molybdenum atom derived from the molybdenum dithiocarbamate (B) is 650 ppm by mass or more on the basis of the whole amount of the lubricating oil composition; a content ratio [C/B.sub.Mo] of the ester-based ashless friction modifier (C) to a molybdenum atom derived from the molybdenum dithiocarbamate (B) is 5.0 to 10 in terms of a mass ratio; the content of a salicylate soap group derived from the metal salicylate (D) is 0.50% by mass or more on the basis of the whole amount of the lubricating oil composition; and a kinematic viscosity at 100° C. is 4.0 mm.sup.2/s or more and less than 9.3 mm.sup.2/s, and a high-temperature high-shear viscosity at 150° C. is 1.7 mPa.Math.s or more and less than 2.9 mPa.Math.s. In accordance with the present invention, a viscosity-reduced lubricating oil composition in which nonetheless a molybdenum dithiocarbamate and an ashless friction modifier are jointly used, not only friction can be reduced early after commencement of lubrication, but also such a state can be maintained, is provided.

The present invention relates to a lubricating oil composition containing a base oil (A), a molybdenum dithiocarbamate (B), an ester-based ashless friction modifier (C), and a metal salicylate (D), wherein the content of a molybdenum atom derived from the molybdenum dithiocarbamate (B) is 650 ppm by mass or more on the basis of the whole amount of the lubricating oil composition; a content ratio [C/B.sub.Mo] of the ester-based ashless friction modifier (C) to a molybdenum atom derived from the molybdenum dithiocarbamate (B) is 5.0 to 10 in terms of a mass ratio; the content of a salicylate soap group derived from the metal salicylate (D) is 0.50% by mass or more on the basis of the whole amount of the lubricating oil composition; and a kinematic viscosity at 100° C. is 4.0 mm.sup.2/s or more and less than 9.3 mm.sup.2/s, and a high-temperature high-shear viscosity at 150° C. is 1.7 mPa.Math.s or more and less than 2.9 mPa.Math.s. In accordance with the present invention, a viscosity-reduced lubricating oil composition in which nonetheless a molybdenum dithiocarbamate and an ashless friction modifier are jointly used, not only friction can be reduced early after commencement of lubrication, but also such a state can be maintained, is provided.

A lubricating oil composition for internal combustion engines containing a base oil (A), a metal-based detergent (B) containing a calcium-based detergent (B1), a zinc dialkyldithiophosphate (C), and a molybdenum-containing compound (D), wherein a calcium atom-equivalent content of the calcium-based detergent (B1) is more than 100 ppm by mass and 600 ppm by mass or less, based on a total amount of the composition, a magnesium atom-equivalent content of a magnesium-based detergent (B2) is less than 200 ppm by mass, based on the total amount of the composition, a sodium atom-equivalent content of a sodium-based detergent (B3) is less than 200 ppm by mass, based on the total amount of the composition, a content ratio of phosphorus derived from the zinc dialkyldithiophosphate (C) to calcium derived from the calcium-based detergent (B1) [P/Ca] is 0.25 or more by mass, and a sulfated ash content is 0.7% by mass or less; and a method for producing the composition.

A lubricating oil composition for internal combustion engines containing a base oil (A), a metal-based detergent (B) containing a calcium-based detergent (B1), a zinc dialkyldithiophosphate (C), and a molybdenum-containing compound (D), wherein a calcium atom-equivalent content of the calcium-based detergent (B1) is more than 100 ppm by mass and 600 ppm by mass or less, based on a total amount of the composition, a magnesium atom-equivalent content of a magnesium-based detergent (B2) is less than 200 ppm by mass, based on the total amount of the composition, a sodium atom-equivalent content of a sodium-based detergent (B3) is less than 200 ppm by mass, based on the total amount of the composition, a content ratio of phosphorus derived from the zinc dialkyldithiophosphate (C) to calcium derived from the calcium-based detergent (B1) [P/Ca] is 0.25 or more by mass, and a sulfated ash content is 0.7% by mass or less; and a method for producing the composition.

The invention addresses a problem of providing a lubricating oil composition for gas engines capable of suppressing viscosity increase while reducing a sulfated ash content and excellent in high-temperature detergency and base number retention. The lubricating oil composition is used for gas engines and contains a base oil (A), at least one ash-free additive (B) selected from an ash-free sulfur-based antioxidant (B1) and a hindered amine compound (B2), and a boronated imide-type dispersant (C), and satisfies the following requirements (X1) to (X3): Requirement (X1): the sulfated ash content is 0.2% by mass or less. Requirement (X2): the content of the ash-free additive (B) is 1.2% by mass or less based on the total amount of the lubricating oil composition, provided that in the case where the ash-free additive (B) contains the hindered amine compound (B2), the content of the hindered amine compound (B2) is less than 1.0% by mass based on the total amount of the lubricating oil composition. Requirement (X3): the content of the boron atom derived from the boronated imide-type dispersant (C) is 200 ppm by mass or more based on the total amount of the lubricating oil composition.

The invention addresses a problem of providing a lubricating oil composition for gas engines capable of suppressing viscosity increase while reducing a sulfated ash content and excellent in high-temperature detergency and base number retention. The lubricating oil composition is used for gas engines and contains a base oil (A), at least one ash-free additive (B) selected from an ash-free sulfur-based antioxidant (B1) and a hindered amine compound (B2), and a boronated imide-type dispersant (C), and satisfies the following requirements (X1) to (X3): Requirement (X1): the sulfated ash content is 0.2% by mass or less. Requirement (X2): the content of the ash-free additive (B) is 1.2% by mass or less based on the total amount of the lubricating oil composition, provided that in the case where the ash-free additive (B) contains the hindered amine compound (B2), the content of the hindered amine compound (B2) is less than 1.0% by mass based on the total amount of the lubricating oil composition. Requirement (X3): the content of the boron atom derived from the boronated imide-type dispersant (C) is 200 ppm by mass or more based on the total amount of the lubricating oil composition.

The durability of a wire rope is improved. The wire rope includes a rope body having at least one strand each formed with a plurality of element wires twisted with each other; a lubricant interposed between the plurality of element wires of the at least one strand; and a resin layer coating the outer periphery of the rope body along with the lubricant, the lubricant containing a sulfur-containing organic molybdenum compound.