The invention provides a method of lubricating a compression-ignition internal combustion engine with a maximum laden mass over 2,700 kg comprising supplying to the engine a lubricating composition comprising: an oil of lubricating viscosity, a 300 TBN or higher alkaline earth metal sulphonate detergent having a metal ratio of 10 to 40, 0.1 wt % to 4 wt % of a borated polyisobutylene succinimide dispersant, wherein the polyisobutylene from which the borated polyisobutylene succinimide is derived has a number average molecular weight of 550 to 1150, and 0.1 wt % to 6 wt % of a polyisobutylene succinimide, wherein the polyisobutylene from which polyisobutylene succinimide is derived has a number average molecular weight of 1550 to 2500, 0 wt % to 0.2 wt % of a phenolic based detergent, wherein the total amount of soap delivered by the alkaline earth metal sulphonate (typically calcium sulphonate) is 0.4 to 1 wt % of the lubricating composition, and wherein the lubricating composition has a sulphated ash content of not more than 1.5 wt %.

The invention provides a method of lubricating a compression-ignition internal combustion engine with a maximum laden mass over 2,700 kg comprising supplying to the engine a lubricating composition comprising: an oil of lubricating viscosity, a 300 TBN or higher alkaline earth metal sulphonate detergent having a metal ratio of 10 to 40, 0.1 wt % to 4 wt % of a borated polyisobutylene succinimide dispersant, wherein the polyisobutylene from which the borated polyisobutylene succinimide is derived has a number average molecular weight of 550 to 1150, and 0.1 wt % to 6 wt % of a polyisobutylene succinimide, wherein the polyisobutylene from which polyisobutylene succinimide is derived has a number average molecular weight of 1550 to 2500, 0 wt % to 0.2 wt % of a phenolic based detergent, wherein the total amount of soap delivered by the alkaline earth metal sulphonate (typically calcium sulphonate) is 0.4 to 1 wt % of the lubricating composition, and wherein the lubricating composition has a sulphated ash content of not more than 1.5 wt %.

A lubricant additive composition including, as a component (A), an organic molybdenum compound represented by general formula (1) described in the specification, and as a component (B), an amine compound represented by general formula (2) described in the specification, wherein content of the component (B) is 1 to 20 parts by mass relative to 100 parts by mass of molybdenum atoms of the component (A), and a lubricating composition containing same.

The invention is directed to a zinc-free lubricating composition for an internal combustion engine containing a phosphorus anti-wear agent, an ashless antioxidant, and an oxyalkylated phenol compound. The lubricating composition provides wear protection, deposit control, and improved acid control with reduced levels of metal-containing additives.

A driveline device is lubricated with a composition of an oil of lubricating viscosity and an oil-soluble quaternary ammonium compound, such as a succinimide or succinamide material or dispersant further containing a quaternary nitrogen atom, and a thiadiazole compound.

A driveline device is lubricated with a composition of an oil of lubricating viscosity and an oil-soluble quaternary ammonium compound, such as a succinimide or succinamide material or dispersant further containing a quaternary nitrogen atom, and a thiadiazole compound.

The present invention relates to novel uses of corrosion inhibitors in fuels and lubricants.

A lubricating composition comprising an oil of lubricating viscosity, 1 to 1000 parts per million by weight of titanium in the form of an oil-soluble titanium-containing material, and at least one additional lubricant additive provides beneficial effects on properties such as deposit control, oxidation, and filterability in engine oils.

A manual transmission oil composition includes: polyisobutenyl succinimide serving as a detergent-dispersant; and comb polymethacrylate (comb PMA), which has at least one of polar and nonpolar branches connected to a main chain thereof, and serves as a viscosity modifier. Polyisobutenyl succinimide is contained in an amount of 1 wt % to 5 wt % based on a total weight of the manual transmission oil composition, W and comb PMA is contained in an amount of 4 wt % to 12 wt % based on the total weight of the manual transmission oil composition.

[Technical Problem] An object is to provide a sliding system that allows the friction coefficient at a sliding part to be considerably reduced by means of a novel combination of a chromium nitride film and a lubricant oil.

[Solution to Problem] The sliding system of the present invention comprises: a pair of sliding members having sliding surfaces that can relatively move while facing each other; and a lubricant oil that can be interposed between the sliding surfaces facing each other. At least one of the sliding surfaces comprises a coating surface of a specific chromium nitride film, and the lubricant oil contains an oil-soluble molybdenum compound comprising molybdenum dialkyldithiophosphate (Mo-DTP). When the chromium nitride film as a whole is 100 at % (referred simply to as %), the chromium nitride film comprises 40-65% of Cr and 35-55% of N and has a relative surface area of 15-85%. The relative surface area is a surface area ratio of a (111) plane to a (200) plane obtained when analyzed with X-ray diffraction. The Mo-DTP is preferably contained at 150-800 ppm as a Mo mass content to the lubricant oil as a whole.