Engine oil \s and methods for use in soot-producing engines. The engine oil contains a major amount of a base oil and a dispersant reaction product of A) a hydrocarbyl-dicarboxylic acid or anhydride, and B) at least one polyamine, that is post-treated with C) an aromatic carboxylic acid, an aromatic polycarboxylic acid, or an aromatic anhydride, wherein all carboxylic acid or anhydride groups of C) are attached directly to an aromatic ring. A molar ratio of carboxyl groups from components A) and C) to nitrogen atoms from component B) of from 0.9 to 1.3 is used to make the dispersant which also has a molar ratio of component C) to component B) of at least 0.4 and when component B) has an average of 4-6 nitrogen atoms per molecule, a molar ratio of A) to B) is from 1.0 to 1.6.

The present invention relates to a lubricating oil composition containing a base oil (A) and a viscosity index improver (B) such that in X-ray small-angle scattering spectra obtained through measurement at 40 C. and 100 C., a ratio [|(40)|/|(100)|] between |(40)| and |(100)|, each of which is an absolute value of a slope of a straight line calculated in a range of the scattering vector q as the x axis of from 0.1 nm .sup.1 to 1 nm .sup.by the least-squares method, is 1.5 or more.

Engine oil \s and methods for use in soot-producing engines. The engine oil contains a major amount of a base oil and a dispersant reaction product of A) a hydrocarbyl-dicarboxylic acid or anhydride, and B) at least one polyamine, that is post-treated with C) an aromatic carboxylic acid, an aromatic polycarboxylic acid, or an aromatic anhydride, wherein all carboxylic acid or anhydride groups of C) are attached directly to an aromatic ring. A molar ratio of carboxyl groups from components A) and C) to nitrogen atoms from component B) of from 0.9 to 1.3 is used to make the dispersant which also has a molar ratio of component C) to component B) of at least 0.4 and when component B) has an average of 4-6 nitrogen atoms per molecule, a molar ratio of A) to B) is from 1.0 to 1.6.

The disclosed technology relates to lubricants for compression ignition internal combustion engines, particularly those demonstrating at least one of improved seals performance, reduced deposit formation, and excellent durability. The present invention provides a low dispersant lubricating composition comprising (a) an oil of lubricating viscosity, (b) about 0.5 weight percent to 3.0 weight percent of an oxyalkylated hydrocarbyl-substituted phenol compound, (c) about 0.01 weight percent to 2.6 weight percent of a polyalkenylsuccinimide dispersant, and (d) about 0.05 weight percent to 2.0 weight percent of a polyolefin dispersant viscosity modifier, and wherein the lubricating composition contains zinc in an amount less than about 700 ppm by weight of the composition.

A lubricant composition having greater than 50 percent by weight of a base oil, a dispersant composition comprising: i) a first dispersant comprising one or more reaction products of at least one polyisobutenyl succinic acid or anhydride having a polyisobutenyl group with a number average molecular weight that is less than or equal to 1300, and at least one polyamine; and ii) a second dispersant comprising one or more reaction products of at least one polyisobutenyl succinic acid or anhydride having a polyisobutenyl group with a number average molecular weight greater than 1300, and at least one polyamine; and at least one ashless antioxidant; and wherein a weight ratio of the second dispersant to the dispersant composition is 0.66:1 to 1:1 or a ratio of the weight percentages of nitrogen contributed by the second dispersant to nitrogen of the dispersant composition is 0.62:1 to 1:1.

The present disclosure relates to emulsifying agents produced from succinic acids or anhydrides and polyalkylene glycols. The present disclosure also relates to lubricating oils containing such emulsifying agents. The emulsifying agent provides a lubricating oil that is substantially free of an aqueous layer after about 24 hours when tested according to ASTM D7563-10.

Method of improving the oxidative stability of a lubricating composition which is used to lubricate a spark ignition internal combustion engine, the spark-ignition engine being comprised within the powertrain of a hybrid electric vehicle, wherein the method comprises the step of introducing into the combustion chamber of the spark-ignition engine a gasoline composition wherein the gasoline composition comprises a hydrocarbon base fuel containing 10 to 20% v olefins, not greater than 5% v olefins of at least 10 carbon atoms, and not greater than 5% v aromatics of at least 10 carbon atoms, based on the base fuel, initial boiling point in the range 30 to 40 C., T10 in the range 45 to 57 C., T50 in the range 82 to 104 C., T90 in the range 140 to 150 C. and final boiling point not greater than 220 C.

The present disclosure relates to emulsifying agents produced from succinic acids or anhydrides and polyalkylene glycols. The present disclosure also relates to lubricating oils containing such emulsifying agents. The emulsifying agent provides a lubricating oil that is substantially free of an aqueous layer after about 24 hours when tested according to ASTM D7563-10.

This invention encompasses lubricating oil compositions comprising a base oil, a biodiesel fuel and a dispersant. A method for inhibiting viscosity increase in a diesel engine fueled at least in part with a biodiesel fuel is also described.

A method of limiting the chemical degradation of hydrocarbonaceous liquids due to nitrogen dioxide contamination at elevated temperature comprises the addition thereto of an ionic liquid composed of a cation and a boron- and halogen-free, multi-functional aromatic anion, the ionic liquid serving to inhibit the nitration of hydrocarbonaceous liquid components that initiates degradation.