A method for improving low temperature performance of a lubricant in a compression-ignited internal combustion engine is disclosed. The method comprises operating the engine with a monograde lubricating oil composition comprising (a) a major amount of a base oil of lubricating viscosity; and (b) a minor amount of an overbased alkaline earth metal salt of an alkyl-substituted hydroxyaromatic compound, the alkyl substituent being a residue derived from an isomerized alpha-olefin having from 12 to 40 carbon atoms per molecule.

A lubricant composition comprising an oil of lubricating viscosity and 0.01 to 5 percent by weight of a substantially sulfur-free alkyl phosphate amine salt, where at least 30 mole percent of the phosphorus atoms are in an alkyl pyrophosphate salt structure, exhibits good antiwear performance. In the phosphate amine salt, at least 80 mole percent of the alkyl groups are typically secondary alkyl groups of 3 to 12 carbon atoms.

Provided is a lubricating oil composition for a gas engine, comprising a base oil (A), a calcium-based detergent (B), and an alkenyl succinimide (C), wherein a content of calcium atoms is 0.09 to 0.17 mass % based on the total amount of the lubricating oil composition, the component (C) comprises a non-boron-modified alkenyl bis-succinimide (C1), and a content of boron atoms derived from the component (C) is less than 0.02 mass % based on the total amount of the lubricating oil composition.

A comb copolymer viscosity modifier may be made by polymerization comprising at least, or consisting essentially of, the following monomers: (a) a hydrogenated polybutadiene-based (alk)acrylate ester macromonomer (which repeat units may comprise from 7.0 wt % to 18 wt % of the repeat units of the comb copolymer viscosity modifier); (b) a C.sub.3-C.sub.8 alkyl (alk)acrylate ester monomer (which repeat units may comprise from 40 wt % to 71 wt % or from 45 wt % to 64 wt % of the repeat units of the comb copolymer viscosity modifier); and (c) a C.sub.12-C.sub.24 alkyl (alk)acrylate ester monomer, wherein repeat units based on the C.sub.12-C.sub.24 alkyl (alk)acrylate ester monomer comprise at least 21.0 wt % (and optionally up to 35.0 wt %) of repeat units of the comb copolymer viscosity modifier. Lubricant compositions comprising the comb copolymer viscosity modifier, as well as uses thereof and methods for modifying viscosity, are also contemplated herein.

A lubricating composition including a polymer blend of a modified styrene-maleic anhydride copolymer and poly(meth)acrylate copolymer effective to maintain a pumpable fluid at low temperatures.

Sulfur-free, ashless, and low phosphorus-containing lubricant compositions for use as engine oil having improved oxidation stability. The lubricant composition can include about 60.0 mass % to about 99.8 mass % of an oil base stock, at least one ashless antiwear additive, at least one ashless detergent, and at least one antioxidant, based on a total mass of the lubricant composition. The oil base stock can include at least one polyalphaolefin and at least one alkyl naphthalene. The lubricant composition can contain less than about 0.05 mass % phosphorus, less than about 0.05 mass % sulfur, and less than about 0.05 mass % ash. The lubricant composition can be made by a process that includes combining the above-mentioned components to provide a lubricant composition.

A lubricant for the hot forming of metals, with respect to the solid constituents, contains at least the following constituents: 55 to 85 wt % of a solid lubricating agent comprising a mixture of talc and a potassium mica, wherein the ratio of talc to potassium mica in the solid lubricating agent is 2.0 to 5.0, 10 to 30 wt % of an adhesive agent selected from a polyvinyl acetate, sodium water glass and dextrin or a mixture of same, 2 to 10 wt % of a thickener selected from hydroxy cellulose, hydroxyethyl cellulose, hydroxyproply cellulose, carboxymethyl cellulose, methyl cellulose, ethyl cellulose, methylethyl cellulose, hydroxyethylmethyl cellulose, hydroxypropylmethyl cellulose, ethylhydroxymethyl cellulose, carboxymethylhydroxy cellulose, dextrin, starch, organically modified bentonite, smectite and xanthan gum, 0 to 10 wt % of further auxiliary agents, and not more than 10 wt % of graphite.

A grease composition may be used for speed reducers and speed increasers, being excellent in both torque transmission efficiency and leak prevention performance. The grease composition may contain a base oil (A) and a urea-based thickener (B), which is used for speed reducers and speed increasers, wherein the particles containing the urea-based thickener (B) in the grease composition satisfy the following requirement (I). Requirement (I): the area-based arithmetic average particle diameter of the particles is 2.0 μm or less, as measured by a laser diffraction/scattering method.

A lubricant composition includes (a) a hydrocarbon oil including at least 30%wt of isoparaffins, based on the total weight of the hydrocarbon oil, and (b) an alkoxylated natural oil. A method of using the lubricant composition in a water- based composition, in particular a water-based mud, to improve the lubricity and/or to reduce the foaming properties of the water-based composition is also disclosed.

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.