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. The dispersants may be made from copolymers having low metal and/or fluorine contents.

A polyisobutylene-substituted hydroxyaromatic compound and derivatives thereof which are suitable for use as additives in lubricating compositions. The polyisobutylene-substituted hydroxyaromatic compound may include the reaction product of a hydroxyaromatic compound with a polyisobutylene having a number average molecular weight of 150 to 800.

A lubricant suitable for lubricating a two-stroke cycle engine which is fueled with a liquid fuel having a volatility less than that of gasoline comprises an oleaginous synthetic ester, a normally liquid solvent having a kinematic viscosity of less than about 5 or 2 mm.sup.2/s at 100 C. and a nitrogen-containing dispersant bearing a hydrocarbyl group of at least 26 carbon atoms and having a nitrogen content of at least 4 percent by weight. The nitrogen content of the lubricant is at least about 0.3 percent by weight.

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 zinc lubricating composition comprising (a) an oil of lubricating viscosity, (b) a borated dispersant, and (c) a metal-free organo-phosphorus anti-wear additive, wherein the lubricating composition is substantially free of a metal containing sulfur coupled alkyl phenol compound. Further, the low zinc lubricating composition contains zinc in an amount less than 600 ppm by weight of the composition.

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 zinc lubricating composition comprising (a) an oil of lubricating viscosity, (b) a borated dispersant, and (c) a metal-free organo-phosphorus anti-wear additive, wherein the lubricating composition is substantially free of a metal containing sulfur coupled alkyl phenol compound. Further, the low zinc lubricating composition contains zinc in an amount less than 600 ppm by weight of the composition.

Provided herein are compositions that include a thiadiazole component and a solubility enhancing component. The solubility enhancing component can include a dispersant, a detergent, or both a dispersant and a detergent. The thiadiazole component can include one or more species having a hydrocarbyl-disulfanyl moiety. The compositions may be used as a corrosion inhibitor. Also provided herein are methods for making a thiadiazole component and a composition.

The present invention provides a lubricant composition comprising a base oil of lubricating viscosity, wherein the base oil comprises an ether base stock of formula (A) where: R.sub.a and R.sub.b are aliphatic hydrocarbyl groups and may be the different; the lubricant composition further comprising from 0.5 to 7% of total dispersant additive, by weight of the lubricant composition. In some embodiments, the ether base stock has the formula (1) where: R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5 and R.sub.6 are as defined herein. The lubricant composition may be used for lubricating a surface in an internal combustion engine as well as for improving the fuel economy performance and/or piston cleanliness performance of an engine and/or a vehicle, such as an automotive vehicle associated with an internal combustion engine.

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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.

A method for preventing or reducing low speed pre-ignition in an engine lubricated with a lubricating oil while maintaining or improving cleanliness by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and at least one boron-containing compound and at least one overbased calcium detergent as minor components. The at least one boron-containing compound includes at least one borated dispersant, or a mixture of a boron-containing compound and a non-borated dispersant. The boron to nitrogen ratio for the at least one boron-containing compound is less than or equal to about 0.3 and the lubricating oil is essentially free of elemental magnesium. The lubricating oils of this disclosure are particularly advantageous as passenger vehicle engine oil (PVEO) products.

A method for preventing or reducing low speed pre-ignition in an engine lubricated with a lubricating oil while maintaining or improving cleanliness by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and at least one boron-containing compound and at least one overbased calcium detergent as minor components. The at least one boron-containing compound includes at least one borated dispersant, or a mixture of a boron-containing compound and a non-borated dispersant. The boron to nitrogen ratio for the at least one boron-containing compound is less than or equal to about 0.3 and the lubricating oil is essentially free of elemental magnesium. The lubricating oils of this disclosure are particularly advantageous as passenger vehicle engine oil (PVEO) products.