A dispersant composition is described. The composition includes a succinimide dispersant composition comprising a reaction product of a hydrocarbyl succinimide and a heteroaromatic glycidyl ether having a structure: ##STR00001## wherein R.sub.1 is a heteroaryl or heteroarylalkyl group having 4 to 20 carbon atoms, and R.sub.2 and R.sub.3 are independently a hydrogen atom, an alkyl group, or an aryl group.

This invention relates to a method of lubricating an internal combustion engine comprising at least one of a crankcase, a gear and a wet-clutch, said method comprising supplying to said crankcase, gear, and wet-clutch a lubricating composition containing: (a) an oil of lubricating viscosity; and (b) a friction modifying additive which is the reaction product of a hydrocarbyl-substituted succinic anhydride and an acid-functionalized amine compound.

This invention relates to a method of lubricating an internal combustion engine comprising at least one of a crankcase, a gear and a wet-clutch, said method comprising supplying to said crankcase, gear, and wet-clutch a lubricating composition containing: (a) an oil of lubricating viscosity; and (b) a friction modifying additive which is the reaction product of a hydrocarbyl-substituted succinic anhydride and an acid-functionalized amine compound.

A method for improving wear control of a steel surface lubricated with a lubricating oil through the generation of thick tribofilms. The method includes: (i) using as the lubricating oil a formulated oil, the formulated oil having a composition comprising at least one lubricating oil base stock as a major component; and at least one lubricating oil additive, as a minor component; and (ii) forming a tribofilm on the steel surface. In time-step tribofilm formation measurements of the lubricating oil by a mini-traction machine (MTM) at constant slide-to-roll ratio (SRR), the saturation traction coefficient (f.sub.s), which correlates to tribofilm thickness on the steel surface, is greater than about 0.11. In the method of this disclosure, elongation of timing chain due to wear of chain link pins is less than about 0.07%, as determined by Ford Chain Wear (FCW) test conducted in accordance with ILSAC GF-6 specification. The lubricating oils are useful in internal combustion engines.

A method for improving wear control, while maintaining or improving deposit control and cleanliness, in an engine or other mechanical component lubricated with a lubricating oil 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 specific combinations of low soap detergents, dispersants, and/or mixtures thereof, as a minor component. The low soap detergents include alkaline earth metal salicylates, alkaline earth metal sulfonates, or mixtures thereof, all having the same or different total base number (TBN). The total amount of soap delivered by the low soap detergent is less than 0.60 weight percent of the lubricating oil. The dispersants include borated and/or non-borated polyisobutylene succinimide (PIMA) having a basic nitrogen content of 1% or greater. The lubricating oils are useful in internal combustion engines.

A method for improving wear control, while maintaining or improving deposit control and cleanliness, in an engine or other mechanical component lubricated with a lubricating oil 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 specific combinations of low soap detergents, dispersants, and/or mixtures thereof, as a minor component. The low soap detergents include alkaline earth metal salicylates, alkaline earth metal sulfonates, or mixtures thereof, all having the same or different total base number (TBN). The total amount of soap delivered by the low soap detergent is less than 0.60 weight percent of the lubricating oil. The dispersants include borated and/or non-borated polyisobutylene succinimide (PIMA) having a basic nitrogen content of 1% or greater. The lubricating oils are useful in internal combustion engines.

A method for improving wear control of a steel surface lubricated with a lubricating oil through the generation of fast-forming tribofilms. The method includes: (i) using as the lubricating oil a formulated oil, the formulated oil having a composition comprising at least one lubricating oil base stock as a major component, and at least one detergent, as a minor component; and (ii) forming a tribofilm on the steel surface. The time for the tribofilm to reach 95% of its saturation coverage (t.sub.95,sat) on the steel surface is less than about 50 minutes, as determined by a high frequency reciprocating rig (HFRR) in accordance with a modified version of ASTM D6079. A lubricating oil including an ester base stock, an alkylated naphthalene base stock, or mixtures thereof, as a major component; and at least one detergent including an alkaline earth metal salicylate, an alkaline earth metal sulfonate, or mixtures thereof, as a minor component.

Provided herein are polyimide dispersants, as well as methods for producing polyimide dispersants. The polyimides can be defined by the formula below

##STR00001##

wherein A, individually for each occurrence, represents a cyclic diimide moiety represented by the structure below

##STR00002##

where B represents a cyclic moiety substituted with a first cyclic imide group and a second cyclic imide group; Y, individually for each occurrence, represents a bivalent linking group; L, individually for each occurrence, is absent or represents a cyclic imide group; R, individually for each occurrence, represents a polymeric tail; and n is an integer from 1 to 20.

The invention relates to the use of at least one triazole compound as an additive for improving the anti-corrosion properties of a lubricant composition for a propulsion system of an electric or hybrid vehicle, said lubricant composition comprising one or more amino and/or sulfur anti-wear additives. The invention also relates to the use of a lubricant composition for lubricating a propulsion system of an electric or hybrid vehicle.

The invention relates to the use of at least one triazole compound as an additive for improving the anti-corrosion properties of a lubricant composition for a propulsion system of an electric or hybrid vehicle, said lubricant composition comprising one or more amino and/or sulfur anti-wear additives. The invention also relates to the use of a lubricant composition for lubricating a propulsion system of an electric or hybrid vehicle.