Abstract: A viscosity index improver containing, in non-ester diluent oil, one or more hydrogenated, functionalized linear block copolymers having at least one block derived from monoalkenyl arene covalently linked to at least one block derived from diene in an amount that is greater than the critical overlap concentration (ch*), in mass %, for the linear block copolymers in the diluent oil; and an amount of ester base stock.

Abstract: A viscosity index improver containing, in non-ester diluent oil, one or more hydrogenated, functionalized linear block copolymers having at least one block derived from monoalkenyl arene covalently linked to at least one block derived from diene in an amount that is greater than the critical overlap concentration (ch*), in mass %, for the linear block copolymers in the diluent oil; and an amount of ester base stock.

Abstract: A viscosity index improver containing, in diluent oil, one or more optionally functionalized linear block copolymers having at least one block derived from alkenyl arene covalently linked to at least one block derived from diene in an amount that is greater than the critical overlap concentration (ch*), in mass %, for the linear block copolymers in the diluent oil; and ester base stock and/or at least one star (or radial) polymer, the star polymer being present in an amount such that the c/ch* value of the star polymer in the concentrate falls within the range of from 0.01 to about 1.6, wherein c is the concentration in mass % of star polymer in the concentrate and ch* is the critical overlap concentration in mass % for the star polymer in the diluent oil used to form the concentrate.

Abstract: A viscosity index improver containing, in diluent oil, one or more optionally functionalized linear block copolymers having at least one block derived from alkenyl arene covalently linked to at least one block derived from diene in an amount that is greater than the critical overlap concentration (ch*), in mass %, for the linear block copolymers in the diluent oil; and ester base stock and/or at least one star (or radial) polymer, the star polymer being present in an amount such that the c/ch* value of the star polymer in the concentrate falls within the range of from 0.01 to about 1.6, wherein c is the concentration in mass % of star polymer in the concentrate and ch* is the critical overlap concentration in mass % for the star polymer in the diluent oil used to form the concentrate.

Abstract: Para-alkylated substituted diphenylamines are made by catalytically alkylating diphenylamine with a branched-chain alkene, such as propene, oligomer mixture in which the oligomer present in the greatest percentage has 15-24 carbon atoms. The alkylated diphenylamines are useful crankcase lubricant additives such as for reducing piston deposits and engine sludge.

Abstract: A method of lubricating a cylinder liner and a crankcase in a marine diesel crosshead engine with the same lubricating oil composition. The lubricating oil composition has a TBN, as measured using ASTM D 2896-98, of 10 to 55 mg KOH/g. The lubricating oil composition comprises: at least 40 mass % of an oil of lubricating viscosity; at least one detergent; at least one dispersant; and at least one anti-wear additive.

Abstract: Para-alkylated substituted diphenylamines are made by catalytically alkylating diphenylamine with a branched-chain alkene, such as propene, oligomer mixture in which the oligomer present in the greatest percentage has 15-24 carbon atoms. The alkylated diphenylamines are useful crankcase lubricant additives such as for reducing piston deposits and engine sludge.

Abstract: A high base number calcium sulphonate detergent having a total soap/BN ratio of 0.0530 to 0.0585, preferably 0.0540 to 0.0580, more preferably 0.0550 to 0.0575. The calcium sulphonate detergent has a base number of greater than 350 mg KOH/g as measured by ASTM D 2896-98. The high base number sulphonate exhibits reduced viscosity drift, improved stability and improved catalytic oxidation.

Abstract: A lubricant composition that exhibits low high temperature high shear viscosity is disclosed. The lubricant composition is made up of a first polymer having a kinematic viscosity ratio less than or equal to 0.25 and a shear stability index (SSI) equal to or greater than 20 percent and base oil having a viscosity index equal to or greater than 120.

Abstract: Use of an oil-soluble hydrocarbyl phenol aldehyde condensate as an antiwear additive in a lubricating oil composition. The oil-soluble hydrocarbyl phenol aldehyde condensate has the following structure: wherein n is 0 to 10, preferably 1 to 8, more preferably 2 to 6, and most preferably 3 to 5; Y is a divalent bridging group, and is preferably a hydrocarbyl group, preferably having from 1 to 4 carbon atoms; and R is a hydrocarbyl group having from 4 to 30, preferably 8 to 18, and most preferably 9 to 15 carbon atoms.

Abstract: A method of lubricating a cylinder liner and a crankcase in a marine diesel crosshead engine with the same lubricating oil composition. The lubricating oil composition has a TBN, as measured using ASTM D 2896-98, of 10 to 55 mg KOH/g. The lubricating oil composition comprises: at least 40 mass % of an oil of lubricating viscosity; at least one detergent; at least one dispersant; and at least one anti-wear additive.

Abstract: A high base number calcium sulphonate detergent having a total soap/BN ratio of 0.0530 to 0.0585, preferably 0.0540 to 0.0580, more preferably 0.0550 to 0.0575. The calcium sulphonate detergent has a base number of greater than 350 mg KOH/g as measured by ASTM D 2896-98. The high base number sulphonate exhibits reduced viscosity drift, improved stability and improved catalytic oxidation.

Abstract: A gas engine lubricating oil composition having a boron content of more than 95 ppm, the gas engine lubricating oil composition comprising: a major amount of a lubricating oil having a viscosity index of 80 to 120, and including at least 90 mass percent of saturates and 0.03 mass percent or less of sulphur; and at least one metal detergent. The gas engine lubricating oil composition exhibits improved oxidation and reduced deposit formation.

Abstract: Lubricating oil compositions for residual fuel oil-fuelled diesel engines for marine and stationary applications comprising, or made by admixing: (a) a basestock of lubricating viscosity, in a major amount; and (b) an oil-soluble or oil-dispersible molybdenum compound, in a minor amount; wherein the oil composition has a TBN from 20 to 100 as measured according to ASTM D-2896 and a viscosity at 100° C. in the range from 9 to 30 mm2 s?1 as measured according to ASTM D-445. The lubricating oil compositions of the present invention demonstrate improved cylinder liner wear performance.

Abstract: A trunk piston marine diesel engine lubricating oil composition is dispersant-free, has a TBN of 25 or greater, and comprises (A) an oil of lubricating viscosity, (B) an aromatic carboxylate as the sole overbased metal detergent, and (C) an antiwear additive.

Abstract: Use of an oil-soluble hydrocarbyl phenol aldehyde condensate as an antiwear additive in a lubricating oil composition. The oil-soluble hydrocarbyl phenol aldehyde condensate has the following structure: wherein n is 0 to 10, preferably 1 to 8, more preferably 2 to 6, and most preferably 3 to 5; Y is a divalent bridging group, and is preferably a hydrocarbyl group, preferably having from 1 to 4 carbon atoms; and R is a hydrocarbyl group having from 4 to 30, preferably 8 to 18, and most preferably 9 to 15 carbon atoms.

Abstract: A marine diesel cylinder lubricant composition having a total base number of at least 30. The composition includes at least 40 weight per cent of an oil of lubricating viscosity, at least one detergent prepared from at least two surfactants, preferably phenate and sulphonate surfactants, at least one boron-containing dispersant providing at least 100 ppm of boron, and at least one zinc-containing antiwear additive, preferably a zinc dihydrocarbyl dithiophosphate, providing at least 230 ppm, preferably at least 250 ppm, of zinc. The marine diesel cylinder lubricant composition exhibits reduced wear even when used with high sulphur fuels.

Abstract: A method of reducing deposit formation in a centrifuge system in a trunk piston diesel engine. The method includes the step of lubricating the trunk piston diesel engine with a trunk piston diesel engine lubricant composition having a total base number of more than 40 mg KOH/g, as determined by ASTM D2896, and including: at least 40 mass % of an oil of lubricating viscosity; at least one detergent, preferably at least two detergents; and at least 1.5 mass % of phenol, based on the total amount of the lubricant composition; with the proviso that if the trunk piston diesel engine lubricant composition includes at least one phenate detergent, the trunk piston diesel engine lubricant composition includes more than 1.7 mass %, preferably more than 1.9 mass %, of phenol.

Abstract: A marine diesel cylinder lubricant composition for a marine diesel engine running on fuel having a sulphur content of less than 1.5%, the composition having a total base number, as determined according to ASTM D2896, of more than 30 and less than 70, and comprising at least 40 wt % of an oil of lubricating viscosity, and at least one detergent prepared from at least two surfactants, one of which is a salicylate. The marine diesel cylinder lubricant composition demonstrates good ability to reduce deposit formation, especially on pistons. The marine diesel cylinder lubricant composition also demonstrates good lubrication at temperatures above 250° C.

Abstract: A gas engine lubricating oil composition that is substantially free from dispersant. The gas engine lubricating oil composition has a TBN in the range of 3.5 to 20. The gas engine lubricating oil composition comprises an oil of lubricating viscosity and at least one metal detergent.