The purpose of the present invention is to provide a lubricant composition which can be applied as a gear oil for a high-output and high-speed gear mechanism, and whereby fuel saving as well as further wear resistance in a bearing of a pinion gear can be realized while maintaining excellent durability, seizure resistance, and stability are maintained. A lubricant composition containing a Fischer-Tropsch-derived base oil, a poly alpha-olefin, and an ester compound, and further containing an unsaturated fatty acid and/or a partial ester compound of an unsaturated fatty acid and a polyol, wherein the partial ester compound of an unsaturated fatty acid includes a monoester compound of an unsaturated fatty acid and a polyol in a ratio of 50% by mass with respect to the total amount of the partial ester compound, and the SAE viscosity grade of the lubricant composition is 75W-85 or lower.

A lubricant composition characterized as having a viscosity of less than about 150,000 cP at −40° C., a kinematic viscosity of less than about 150,000 cSt at −40° C., and a kinematic viscosity of at least about 18.5 cSt at 100° C. for use in association with a device involving metal to metal contact of moving parts comprising: (a) base-stock comprising (i) at least one relatively low viscosity polyalphaolefin, (ii) at least one ester, and at least one Group III base oil; (b) viscosity improver comprising (i) at least one relatively high viscosity polyalphaolefin, and (ii) a least one olefin copolymer; (c) a performance additive comprising at least one additive effective to improve at least one property of the lubricant and/or the performance of the equipment in which the lubricant is to be used; (d) at least one pour-point depressant; and, optionally, (e) at least one antifoam agent.

The invention provides a grease composition used for lubricating a mechanical part having a steel portion to be lubricated which performs a rolling motion and a rolling and sliding motion, containing a base oil, a thickener and an additive, wherein the additive includes at least one compound selected from the group consisting of polyethylene wax, oxidized polyethylene wax, polypropylene wax, montan wax and amide wax.

The present disclosure describes transmission fluid compositions, additive packages, and methods for lubricating a transmission, particularly transmission fluid compositions having color stability that are able to meet or exceed vehicle transmission fluid specifications for different makes of vehicles. The transmission fluid composition contains a base oil and an additive composition having at least one thiadiazole compound the selected from compounds of the Formulas (I)-(II):

##STR00001##

wherein n is 1-5; R.sup.1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R.sup.2 is a hydrogen or is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms, wherein the transmission fluid composition is adapted for use in a transmission.

A lubricating oil composition of the invention contains: a base oil; at least one of acid phosphate represented by formulae (1) and (2) below; and an antioxidant.

##STR00001##

In the above formulae: R.sup.1, R.sup.2 and R.sup.3 are alkyl groups; and at least one of R.sup.1 and R.sup.2 has 20 to 30 carbon atoms while R.sup.3 has 20 to 30 carbon atoms.

A lubricant composition comprising an oil of lubricating viscosity and an N-hydrocarbyl-substituted aminoester, wherein the N-hydrocarbyl substituent comprises a hydrocarbyl group of at least 3 carbons atoms, with a branch at the 1 or 2 position of the hydrocarbyl chain, provides good iron and copper corrosion performance in driveline or gear applications.

A lubricating composition includes an oil of lubricating viscosity and a low-ash additive system including a low molecular weight amine with a Total Base Number of at least 150, and an N-substituted hydrocarbyl-substituted succinimide dispersant. The low-ash additive system provides the lubricating composition with a significant boost in TBN without substantially lowering the flashpoint. The composition is particularly suited to use as a marine diesel engine lubricant.

A lubricant composition for application onto a surface of drive elements includes: a base oil; and a silasesquioxane. In an embodiment, the silasesquioxane has the chemical formula [RSiO3/2].sub.n with: n=6, 8, 10, 12; where R independently of one another=alkyl (C1-C20), cycloalkyl (C3-C20), alkenyl (C2-C20), cycloalkenyl (C5-C20), alkynyl (C2-C20), cycloalkynyl (C5-C20), aryl (C6-C18) or heteroaryl group, oxy, hydroxy, alkoxy (C4-C10), oxirane polymer (degree of polymerization with 4 to 20 repeat units), carboxy, silyl, alkylsilyl, alkoxysilyl, siloxy, alkylsiloxy, alkoxysiloxy, silylalkyl, alkoxysilylalkyl, alkylsilylalkyl, halogen, epoxy (C2-C20), ester, aryl ether, fluoroalkyl, blocked isocyanate, acrylate, methacrylate, mercapto, nitrile, amine, and/or phosphine group, each substituted or unsubstituted.

A power transmitting fluid comprises a major amount of a lubricating oil and a minor amount of an additive composition. The additive composition comprises: (a) a friction modifier of the formula: ##STR00001## (b) an oil-soluble phosphorus compound; and, (c) an ashless dispersant;
wherein R.sup.1 and R.sup.2 may be the same or different and represent linear or branched, saturated or unsaturated hydrocarbyl groups having from 8 to 20 carbon atoms. Z represents a polyoxyalkylene segment or a polyalkoxylated alkyl amine segment. The friction modifiers provide the fluid with improved fluoroelastomer seal compatibility and enhanced copper corrosion compatibility.

Disclosed is a method for preparing a low-viscosity oil including more than 50 wt % of 9-methyl-11-octyl-heneicosane. The method uses a specific metallocene catalyst and makes it possible to prepare a polyalphaolefin oil (PAO) in which the kinematic viscosity at 100° C., measured according to standard ASTM D445, ranges from 3 to 4 mm.sup.2/s.sup.−1. The oil can be used as a high-performance lubricant for lubrication in the fields of engines, gears, brakes, hydraulic fluids, coolants and greases