An automatic transmission fluid comprises a major amount of an oil of lubricating viscosity and minor amounts of (a) one or more oil-soluble or dispersible molybdenum-containing compounds, and (b) a reaction product of an isomerized alkenyl-substituted succinic anhydride and a polyamine characterized by structure (II):

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In structure (II) x and y are independently zero or integers from 1 to 30, where x+y is from 1 to 30, and z is zero or an integer from 1 to 10.

Provided are a lubricating oil composition containing a base oil, a specific thiophosphate compound (A) and a molybdenum-based compound (B), which exhibits excellent wear resistance and has a low friction coefficient in a broad range of contact pressures ranging from high to low; and a precision reduction gear using the lubricating oil composition.

Provided are a lubricating oil composition containing a base oil and a specific thiophosphate compound (A) and not substantially containing a molybdenum-based, and a precision reduction gear using the lubricating oil composition. The lubricating oil composition and the precision reduction gear using it exhibit excellent wear resistance and can prevent sludge generation in a broad range of contact pressures ranging from high to low.

A grease composition may contain a base oil (A) and a urea-based thickener (B). Particles containing the urea-based thickener (B) in the grease composition may satisfy requirement (I). The base oil (A) may be a mixed base oil containing a high-viscosity base oil (A1) having a kinematic viscosity at 40? C. of 250 mm.sup.2/s to 550 mm.sup.2/s, a low-viscosity base oil (A2) having a kinematic viscosity at 40? C. of 5.0 mm.sup.2/s to 110 mm.sup.2/s, and an ultra-high viscosity hydrocarbon-based synthetic oil (A3) having a number average molecular weight (Mn) of 2,500 to 4,500 and a kinematic viscosity at 40? C. of 25,000 mm.sup.2/s to 50,000 mm.sup.2/s. The base oil (A) may have a kinematic viscosity at 40? C. of 25 mm.sup.2/s to 105 mm.sup.2/s and a viscosity index of 120 or more. Both low-temperature characteristics and a lubricating life can be achieved.

The invention addresses a problem of providing a lubricating oil composition for gas engines capable of suppressing viscosity increase while reducing a sulfated ash content and excellent in high-temperature detergency and base number retention. The lubricating oil composition is used for gas engines and contains a base oil (A), at least one ash-free additive (B) selected from an ash-free sulfur-based antioxidant (B1) and a hindered amine compound (B2), and a boronated imide-type dispersant (C), and satisfies the following requirements (X1) to (X3): Requirement (X1): the sulfated ash content is 0.2% by mass or less. Requirement (X2): the content of the ash-free additive (B) is 1.2% by mass or less based on the total amount of the lubricating oil composition, provided that in the case where the ash-free additive (B) contains the hindered amine compound (B2), the content of the hindered amine compound (B2) is less than 1.0% by mass based on the total amount of the lubricating oil composition. Requirement (X3): the content of the boron atom derived from the boronated imide-type dispersant (C) is 200 ppm by mass or more based on the total amount of the lubricating oil composition.

Novel compounds are described, being alkylated diphenylamine derivatives of triazole, wherein the alkyl group on at least one of the phenyl groups is C8 or higher, in an amount ranging from 0.001 to 5.0% by weight of the lubricating composition. In particular, the derivatives may be 1-[di-(4-octylphenyl)aminomethyl]triazole; 1-[di-(4-nonylphenyl)aminomethyl]triazole; 1-[(4-octylphenyl)(4-butylphenyl)aminomethyl]triazole; and 1-[(4-octylphenyl)(phenyl)aminomethyl]triazole. A lubricating composition comprising the novel derivatives is also disclosed.

An oleaginous corrosion-resistant lubricating composition comprising at least one poly-alpha olefin synthetic oil and effective amounts of metal salts of sulfonic acids, metal salts of carboxylic acids, metal salts of mixtures of said sulfonic and carboxylic acids, alkylated aromatic stabilizers as solubility modifiers, pour-point depressants, at least one antioxidant, triazole deactivator compounds and fluoroacrylate copolymers.

The invention provides a lubricating composition containing an oil of lubricating viscosity and an ashless thiocarbamate compound having an optionally-substituted hydrocarbyl group on an S-atom and an optionally-substituted hydrocarbyl group on an N-atom. The invention further relates to a method of the lubricating an internal combustion engine with the lubricating composition.

An oleaginous corrosion-resistant lubricating composition comprising at least one poly-alpha olefin synthetic oil and effective amounts of metal salts of sulfonic acids, metal salts of carboxylic acids, metal salts of mixtures of said sulfonic and carboxylic acids, alkylated aromatic stabilizers as solubility modifiers, pour-point depressants, at least one antioxidant, triazole deactivator compounds and fluoroacrylate copolymers.

A fluid contains a base oil and an antioxidant, the base oil consisting of sulfur-containing polyalkylene glycol where greater than 80 weight-percent of the fluid is a sulfur-containing polyalkylene glycol and less than one weight-percent of the fluid is water, with weight percent based on total fluid weight an wherein the sulfur-containing polyalkylene glycol is free of oxygen bound directly to sulfur.