A method of reducing the incidence of deposits on the pistons of a 4-stroke marine diesel engine during operation of the engine when it is fuelled with a marine residual fuel meeting the ISO 8217 2017 fuel standard for marine residual fuels and having a sulphur content of more than 0.1% and less than 0.5% by mass. The method includes the step of lubricating the engine using a lubricating oil composition comprising: a) at least 50% by mass, based on the mass of the composition, of an oil of lubricating viscosity; (b) 5 to 25% by mass, based on the mass of the composition, of an oil-soluble or oil-dispersible alkali metal or alkaline earth metal salicylate detergent, or a mixture of two or more oil-soluble or oil-dispersible alkali metal or alkaline earth metal salicylate detergents; (c) 0.1 to 10% by mass, based on the mass of the composition of one or more oil-soluble or oil-dispersible ashless dispersants; and optionally, (d) 0.1 to 10% by mass, based on the mass of the composition of a polyalkylene-substituted succinic anhydride.

The present disclosure relates to a lubricating fluid for an electric motor system and a method of lubricating gears and cooling a motor in an electric motor system. In particular, the disclosed technology relates to a lubricating fluid, for use in electric motor vehicle, comprising an oil of lubricating viscosity and at least one phosphorylated dispersant exhibiting increased resistivity after aging.

The present disclosure relates to a lubricating fluid for an electric motor system and a method of lubricating gears and cooling a motor in an electric motor system. In particular, the disclosed technology relates to a lubricating fluid, for use in electric motor vehicle, comprising an oil of lubricating viscosity and at least one phosphorylated dispersant exhibiting increased resistivity after aging.

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 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; 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.

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; 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.

A lubricating oil composition for internal combustion engines is disclosed. The composition exhibits a lower coefficient of friction and improved cleaning properties without causing a deterioration in thermal and oxidation stability.

A lubricating oil composition for internal combustion engines is disclosed. The composition exhibits a lower coefficient of friction and improved cleaning properties without causing a deterioration in thermal and oxidation stability.

Disclosed is a lubricating oil composition. The lubricating oil composition contains a lubricating base oil including mineral base oil, 4 to 15 mass % of an ester compound of a monovalent or polyvalent aliphatic carboxylic acid and a monovalent or polyvalent aliphatic alcohol, 400 to 1200 mass ppm of zinc dialkyl dithiophosphate in terms of a phosphorus element, 500 to 3000 mass ppm of a calcium-based detergent in terms of a calcium element, and 50 to 1000 mass ppm of a boron-modified succinimide-based dispersant in terms of a boron element, on the basis of the total amount of the lubricating oil composition.

Disclosed is a lubricating oil composition. The lubricating oil composition contains a lubricating base oil including mineral base oil, 4 to 15 mass % of an ester compound of a monovalent or polyvalent aliphatic carboxylic acid and a monovalent or polyvalent aliphatic alcohol, 400 to 1200 mass ppm of zinc dialkyl dithiophosphate in terms of a phosphorus element, 500 to 3000 mass ppm of a calcium-based detergent in terms of a calcium element, and 50 to 1000 mass ppm of a boron-modified succinimide-based dispersant in terms of a boron element, on the basis of the total amount of the lubricating oil composition.