A method for minimizing power loss, reducing a fuel consumption and/or for reducing and/or avoiding deposits in a fuel system in the direct injection diesel engines. The method contains adding a copolymer to a fuel composition, wherein the copolymer contains, in a copolymerized form: (A) an ethylenically unsaturated mono- or dicarboxylic acid or a derivative thereof, (B) an -olefin having from 12 to 30 carbon atoms, (C) optionally an additional aliphatic or cycloaliphatic olefin which has at least 4 carbon atoms and is different from monomer (B) and (D) optionally an additional copolymerizable monomers other than monomers (A), (B) and (C), anhydride or carboxylic acid functionalities present in the copolymer are partly reacted with at least one compound (E) comprising an alcohol group and/or an amino group, and the anhydride functionalities present in the copolymer are hydrolysed and/or carboxylic ester functionalities present in the copolymer are partly hydrolyzed.

A lubricating oil composition may contain a base oil (A) and a dispersant-type viscosity index improver (B), in which the nitrogen atom content based on the solid content of the dispersant-type viscosity index improver (B) is 0.50 to 1.50% by mass, and the weight-average molecular weight (Mw) thereof is 100,000 or more, and the content in terms of the solid content based on the total amount of the composition of the dispersant-type viscosity index improver (B) is more than 0.05% by mass and less than 5.0% by mass. The lubricating oil composition may exert excellent wear resistance in a state contaminated with soot.

A lubricating oil composition may contain a base oil (A) and a dispersant-type viscosity index improver (B), in which the nitrogen atom content based on the solid content of the dispersant-type viscosity index improver (B) is 0.50 to 1.50% by mass, and the weight-average molecular weight (Mw) thereof is 100,000 or more, and the content in terms of the solid content based on the total amount of the composition of the dispersant-type viscosity index improver (B) is more than 0.05% by mass and less than 5.0% by mass. The lubricating oil composition may exert excellent wear resistance in a state contaminated with soot.

Selected comb polymers contain specified amounts of macromonomer and nitrogen-containing (meth)acrylates. Lubricant compositions can contain such comb polymers. The selected comb polymers can be used as solubilizers in lubricant compositions, especially in engine oil (EO) compositions.

Selected comb polymers contain specified amounts of macromonomer and nitrogen-containing (meth)acrylates. Lubricant compositions can contain such comb polymers. The selected comb polymers can be used as solubilizers in lubricant compositions, especially in engine oil (EO) compositions.

A lubricating composition includes an oil of lubricating viscosity and an oil-soluble dispersant viscosity modifier. The dispersant viscosity modifier includes an olefin-based polymer backbone and at least one pendent group derived from a functionalized aliphatic amine. Each pendent group is independently attached to the olefin-based polymer backbone. The pendent group is non-ionic, non-basic, and non-acidic and includes a functional group which includes at least one heteroatom other than nitrogen.

A lubricating composition includes an oil of lubricating viscosity and an oil-soluble dispersant viscosity modifier. The dispersant viscosity modifier includes an olefin-based polymer backbone and at least one pendent group derived from a functionalized aliphatic amine. Each pendent group is independently attached to the olefin-based polymer backbone. The pendent group is non-ionic, non-basic, and non-acidic and includes a functional group which includes at least one heteroatom other than nitrogen.

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.

The present invention provides a multiple function dispersant viscosity index improver, a method of making the multiple function dispersant viscosity index improver, and a lubricating oil comprising the multiple function dispersant viscosity index improver. The multiple function dispersant viscosity index improver comprises two different functional groups, each directly grafted to a polymer backbone having graftable sites. The first functional group comprises the reaction product of an acylating agent and a first amine, the first amine comprising an aromatic primary amine, and the second functional group comprises the reaction product of an acylating agent and a second amine, the second amine comprising an aliphatic primary amine. The first functional group provides the dispersant viscosity index improver with soot handling performance attributes and the second functional group provides the dispersant viscosity index improver with sludge and varnish control performance attributes.