The purpose of the present invention is to provide a lubricating oil composition capable of achieving good wear resistance and good scoring resistance of a bearing in addition to further fuel saving while maintaining durability and seizure resistance that can be used as a gear oil for a high-output, high-speed gear mechanism. A lubricating oil composition containing a combination of Fischer-Tropsch derived base oil having a low kinematic viscosity at high temperature, polyalphaolefin having a high kinematic viscosity at high temperature, and ester compound of a trivalent or higher polyol having a low kinematic viscosity at high temperature, and further contains a partial ester compound of an unsaturated fatty acid and a polyol, including a monoester compound of the unsaturated fatty acid and the polyol.

Lubricating oil compositions are disclosed. The lubricating oil compositions include one or more base oils (A) containing one or more polyalphaolefin (PAO) base oils derived at least in part from a C.sub.12 olefin. The lubricating oil compositions further include from about 65 wt. % to about 85 wt. %, based on the total weight of the lubricating oil composition, of one or more base oils (B) having a kinematic viscosity at 100° C. of from about 3.0 cSt to about 5.5 cSt; and from about 0.1 wt. % to about 10 wt. %, based on the total weight of the lubricating oil composition, of a succinimide dispersant.

Provided is a grease composition for a ball joint that can reduce the wear of a ball seat at a slide region and also has excellent compatibility with a dust cover. The grease composition for a ball joint comprises a base oil, a thickener, and an additive. The base oil contains an ethylene-α-olefin copolymer and the kinetic viscosity of the base oil at 40° C. is 2,000 to 6,000 mm.sup.2/s. The additive contains a polar wax (e.g., monoamide wax or ester wax).

Disclosed is a lubricating oil composition capable of having a good balance of electrical insulation, seizure resistance and wear resistance. In particular, the lubricating oil composition comprises: (A) a lubricant base oil; (B) an alkaline earth metal detergent; (C) a triazole-based compound represented by the following general formula (1) or (2): ##STR00001##
wherein R.sup.1-R.sup.6 are as defined herein; (D) at least one sulfur-containing compound selected from the group consisting of a sulfur-containing heterocyclic ether compound and a sulfide compound; and (E) an ashless dispersant.

A lubricant composition comprising, in relation to the total weight of the lubricant composition:

at least one base oil;

0.005 to 10% by weight of at least one polymeric organic friction modifier; and

0.005 to 10% by weight of at least one ester, said polymeric organic friction modifier being the reaction product of: a) at least one hydrophobic polymer subunit which comprises a hydrophobic polymer selected from polyolefins, polyacrylics and polystyrenes; b) at least one hydrophilic polymer subunit which comprises a hydrophilic polymer selected from polyethers, polyesters and polyamides; c) optionally at least one backbone moiety capable of linking polymeric subunits together; and d) optionally a chain termination group.

The present invention provides a non-aqueous lubricant composition comprising a base stock and 5 at least 0.02 wt % of a friction reducing additive which comprises a block co-polymer of at least one block A which is an oligo- or polyester residue of a hydroxycarboxylic acid and at least one block B which is a residue of a polyalkylene glycol. The invention also provides the use of a block co-polymer of at least one block A which is an oligo- or polyester residue of a hydroxycarboxylic acid and at least one block B which is a residue of a polyalkylene glycol to reduce the kinetic co-efficient 10 of friction in a non-aqueous lubricant composition when compared to an equivalent lubricant composition comprising no block co-polymer.

The instant disclosure generally relates to lubricating compositions having an oil of lubricating viscosity, a mixture of boron-containing and boron-free dispersants, an overbased magnesium-based detergent, an overbased calcium-based detergent, an ashless friction modifier, and, optionally, other performance additives. The instant lubricating compositions may improve one or more of cleanliness, TBN retention, fuel economy and low-speed preignition (“LSPI”).

An apparatus for preparing polyalpha-olefins includes a mixing unit, a microchannel reaction unit, a high-pressure separation unit, a low-pressure separation unit, a gas circulation unit, a post-treatment unit and a pressure control unit, the mixing unit, the microchannel reaction unit, the high-pressure separation unit, the low-pressure separation unit that are successively connected. The gas circulation unit, the microchannel reaction unit is provided with the BF.sub.3 gas inlet, the mixing unit is provided with the auxiliary feed inlet, and the olefin raw material inlet, the gas circulation unit is connected with the BF.sub.3 gas inlet, the low-pressure separation unit is further connected with the post-treatment unit, and the high-pressure separation unit, the pressure control unit, and the gas circulation unit are further successively connected. The apparatus has the advantages of high polymerization reaction speed, high reaction conversion and good product selectivity, and is suitable for large-scale industrial production.

There is provided a grease composition for improving the chemical stability of the grease composition and increasing the fatigue life of a member in which the grease composition is used. The problems can be solved by a grease composition including a poly-α-olefin; a urea-based thickener; molybdenum dithiophosphate; and barium sulfonate, wherein a difference between an SP value of the urea-based thickener and an SP value of the poly-α-olefin is 3.5 or less.

The present invention provides a class of halogen-containing synthetic base oils, and preparation method and use thereof. The synthetic base oils have introduced with halogen, especially fluorine, wherein the dipole motion of the halogen groups results in dipole interaction between the dipoles of other components and the base oil molecules of dipole-dipole and dipole-induced halogen (especially fluorine), and the interaction force is stronger and more localized than the dispersion force between the molecules of pure hydrocarbon synthetic oils, and thus the performance of the base oils is directly affected. It solved the problem of oil solubility of pure hydrocarbon synthetic oils, and also improved the properties of oxidation resistance and thermal stability.