A method for preventing or reducing engine knock or pre-ignition in a high compression spark ignition engine lubricated with a lubricating oil by introducing to a combustion chamber of the engine from 0.1 to 5% by volume of the gasoline used a lubricating oil as a formulated oil, said formulated oil having a composition comprising (i) a major amount of a lubricating oil base stock comprising at least 80% by weight of one branched ester having at least 15% of the total carbons in the form of methyl groups, and (ii) a minor amount of at least one ashless amine phosphate antiwear additive. Also provided is a lubricating engine oil for high compression spark ignition engines including (i) a major amount of a lubricating oil base stock comprising at least 80% by weight formula I below:

##STR00001##

esterified (per OH basis) with 25 to 100% isobutyric acid and 0 to 75% 3,5,5-trimethylhexanoic acid, wherein R is a H, methyl, ethyl, isopropyl, or isobutyl, and (ii) a minor amount of at least one amine phosphate ashless antiwear additive.

A method for preventing or reducing engine knock or pre-ignition in a high compression spark ignition engine lubricated with a lubricating oil by introducing to a combustion chamber of the engine from 0.1 to 5% by volume of the gasoline used a lubricating oil as a formulated oil, said formulated oil having a composition comprising (i) a major amount of a lubricating oil base stock comprising at least 80% by weight of one branched ester having at least 15% of the total carbons in the form of methyl groups, and (ii) a minor amount of at least one ashless amine phosphate antiwear additive. Also provided is a lubricating engine oil for high compression spark ignition engines including (i) a major amount of a lubricating oil base stock comprising at least 80% by weight formula I below:

##STR00001##

esterified (per OH basis) with 25 to 100% isobutyric acid and 0 to 75% 3,5,5-trimethylhexanoic acid, wherein R is a H, methyl, ethyl, isopropyl, or isobutyl, and (ii) a minor amount of at least one amine phosphate ashless antiwear additive.

A lubricating oil composition for industrial machines containing a base oil (A) and a specific acylglycerol (B) and having excellent brake squeal preventing performance, and a lubrication method using the composition.

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.

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.

An oleaginous nanoparticle dispersion of nanoparticles having a core of an organic base material immobilized within a surfactant layer, the use thereof as a low ash, or ash-free source of TBN in lubricating oil compositions, and lubricating oil compositions formulated with such oleaginous nanoparticle dispersions.

An oleaginous nanoparticle dispersion of nanoparticles having a core of an organic base material immobilized within a surfactant layer, the use thereof as a low ash, or ash-free source of TBN in lubricating oil compositions, and lubricating oil compositions formulated with such oleaginous nanoparticle dispersions.

A stable lubricant emulsion composition for use in engine and gear applications is provided. The emulsion includes a base petroleum oil, an aqueous salt solution that functions as a friction/wear modifier, and a polymeric non-ionic surfactant composition having a hydrophilic-lipophilic balance value in the range of 2.5 to 7 and an average molecular weight in the range of 1,000 to 3,000. The surfactant composition may include a polyester surfactant, a PIB succinimide surfactant, a PIB amine surfactant, or a mixture thereof.

A stable lubricant emulsion composition for use in engine and gear applications is provided. The emulsion includes a base petroleum oil, an aqueous salt solution that functions as a friction/wear modifier, and a polymeric non-ionic surfactant composition having a hydrophilic-lipophilic balance value in the range of 2.5 to 7 and an average molecular weight in the range of 1,000 to 3,000. The surfactant composition may include a polyester surfactant, a PIB succinimide surfactant, a PIB amine surfactant, or a mixture thereof.

Ethylene-C.sub.3-C.sub.10 alpha olefin copolymers, dispersants and lubricating oils/fuel compositions incorporating dispersants, and related methods are generally described herein. The copolymer may comprise ethylene-derived units and C.sub.3-C.sub.10 alpha-olefin-derived units. The C.sub.3-C.sub.10 alpha-olefin-derived units may have a carbon number from three to ten. For example, the C.sub.3-C.sub.10 alpha-olefin-derived units may be propylene-derived units.