The invention provides a lubricating composition containing (a) an oil of lubricating viscosity, (b) a phosphite having at least one hydrocarbyl group that has 4 or more carbon atoms, and (c) a compound derived from a hydroxy-carboxylic acid. The invention further relates to the use of the lubricating composition in an internal combustion engine.

A lubricating oil composition for automotive transmissions is disclosed. It offers an automotive transmission (especially a fuel-saving type) which satisfies all requirements as regards the properties of resistance to churning, maintenance of the oil film and low-temperature viscosity. It comprises a GTL low viscosity base oil and a Group 1 high viscosity base oil.

Lubricant compositions, core-shell nanoparticles, and related methods are disclosed. In an exemplary embodiment, a lubricant composition includes a plurality of core-shell nanoparticles. The nanoparticles include a core, a first shell disposed on the core, and a second shell disposed on the first shell. The first shell is formed from a siliceous material and the second shell is formed from a hydrophobic material. The first and second shells form functional coatings that reduce wear and friction of parts lubricated with the lubricant composition.

The invention provides a lubricating composition containing an oil of lubricating viscosity and a sulfurized aromatic amine compound, especially sulfur coupled aniline. The invention further relates to methods of lubricating an internal combustion engine by supplying the described lubricating composition to the internal combustion engine. The invention further relates to the use of the sulfurized aromatic amine compound as a TBN booster and an antioxidant.

The invention provides a lubricating composition comprising an oil of lubricating viscosity, 0.1 wt % to 10 wt % of an overbased detergent, and 0.01 wt % to 5 wt % of a non-hydroxy terminated acylated polyalkylene oxide. The invention further relates to a method of lubricating a mechanical device (such as an internal combustion engine) with the lubricating composition. The invention further relates to the use of the non-hydroxy terminated acylated polyalkylene oxide to provide at least one of (i) improved sludge handling, (ii) reduced lead or copper corrosion, (iii) increased oxidation resistance, (iv) improved acid control, (v) reduced wear (such as cam wear or lifter wear), (vi) retention of total base number of the lubricant, and/or (vii) improved seal compatibility in an internal combustion engine.

A lubricant composition includes an oil of lubricating viscosity and a 4-hydroxybenzamide as a friction modifier. The lubricant composition has a kinematic viscosity at 100° C. of from 5 to 18 mm2/s.

The invention provides a lubricating composition containing an oil of lubricating viscosity, an ashless thiocarbamate compound having an optionally-substituted hydrocarbyl group on an S-atom and an optionally-substituted hydrocarbyl group on an N-atom, and a boron-containing compound. The invention further relates to a method of lubricating an internal combustion engine with the lubricating composition.

A lubricant composition of an oil of lubricating viscosity; an esterified copolymer with a backbone comprising units derived from (i) an α-olefin monomer of at least about 6 carbon atoms and (ii) an ethylenically unsaturated carboxylic acid in a mole ratio of 1:3 to 3:1; and a polymer comprising olefin monomer units of 3 to 5 carbon atoms, wherein at least 50 percent by weight of such units contain fewer than 6 carbon atoms and wherein less than 5 percent by weight of such units are ethylene monomer units; exhibits good power transfer efficiency and elastohydrodynamic film thickness.

A lubricating oil composition including: a lubricant base oil; (A) a calcium salicylate detergent in an amount of 0.005 to 0.03 mass % in terms of calcium on the basis of the total mass of the composition; and (B) a phosphite ester compound represented by the following general formula (1) in an amount of 0.01 to 0.06 mass % in terms of phosphorus on the basis of the total mass of the composition:

##STR00001##

wherein in the general formula (1), R.sup.1 and R.sup.2 are each independently a C5-20 group represented by the following general formula (2):

##STR00002##

wherein in the general formula (2), R.sup.3 is a C2-17 linear chain hydrocarbon group, and R.sup.4 is a C3-17 linear chain hydrocarbon group, and X.sup.1 is an oxygen atom or a sulfur atom.

A lubricating oil composition for automotive transmissions is disclosed. It offers an automotive transmission (especially a fuel-saving type) which satisfies all requirements as regards the properties of resistance to churning, maintenance of the oil film and low-temperature viscosity. It comprises a GTL low viscosity base oil and a Group 1 high viscosity base oil.