Abstract: The invention provides terpolymers of ethylene, at least one ethylenically unsaturated ester and propene, which a) contain from 12.0 to 16.0 mol % of structural units derived from at least one ethylenically unsaturated ester, b) contain from 1.0 to 4.0 methyl groups derived from propene per 100 aliphatic carbon atoms, and c) have fewer than 6.5 methyl groups stemming from chain ends per 100 CH2 groups. and also their use as cold additives for middle distillates.

Abstract: A method for preventing or inhibiting exhaust valve seat recession in a natural gas fueled engine, the method comprising lubricating the engine with a natural gas engine lubricating oil composition comprising (a) a major amount of an oil of lubricating viscosity; and (b) an alkali metal-containing detergent, wherein the natural gas engine lubricating oil composition is substantially free of each of any alkaline earth metal-containing detergents and lithium-containing detergents is disclosed.

Abstract: The invention provides additive mixtures comprising A) at least one terpolymer of ethylene, propene and at least one ethylenically unsaturated ester, which i) contains from 6.0 to 12.0 mol % of structural units derived from at least one ethylenically unsaturated ester having a C1- to C3-alkyl radical, ii) contains from 0.5 to 4.0 methyl groups derived from propene per 100 aliphatic carbon atoms, iii) has fewer than 8.0 methyl groups stemming from chain ends per 100 CH2 groups, and B) from 0.5 to 20 parts by weight, based on A), of at least one further component which is effective as a cold additive for mineral oils and is selected from B1) copolymers of ethylene and ethylenically unsaturated compounds whose content of ethylenically unsaturated compounds is at least 2 mol % higher than the content of ethylenically unsaturated esters in the terpolymer defined under A), B2) comb polymers, and B3) mixtures of B1) and B2), and also their use as a cold additive for middle distillates.

Abstract: This invention relates to a hydroxyaromatic functionalized polyalpha-olefin comprising the product of the combination of: a) a polyalpha-olefin comprising one or more C3 to C20 linear alpha-olefins and having at least 10% vinylidene unsaturation, a viscosity index of 80 to 400, an Mn of 300 to about 20,000, and a pour point of 0° C. or less; and b) a hydroxyaromatic moiety; wherein the analine point of the functionalized polyalpha-olefin is at least 10° C. lower than the analine point of the polyalpha-olefin.

Abstract: The present invention provides a grease composition or a lubricating oil composition which is capable of effectively preventing hydrogen brittleness-caused peeling from occurring on a rolling surface of a rolling bearing, is excellent in durability in a high temperature and speed operation, and can be used for a long time. A grease-packed bearing (1) has an inner ring (2), an outer ring (3), and a plurality of rolling elements (4). A sealing member (6) for sealing a grease composition (7) is provided at openings (8a) and (8b) disposed at both axial ends of the inner ring (2) and the outer ring (3). The grease composition (7) includes a base grease composed of a base oil and a thickener and an additive added to the base grease. The additive contains at least one compound selected from among plant-derived polyphenolic compounds and compounds formed by decomposition thereof.

Abstract: Provided is a method of improving nitrile seal compatibility with a lubricating oil in an engine lubricated with the lubricating oil. The method includes using as the lubricating oil a formulated oil comprising a lubricating oil base stock as a major component and an alkylated aromatic base stock as a minor component. Nitrile seal compatibility is improved as compared to nitrile seal compatibility achieved using a lubricating oil containing a minor component other than the alkylated aromatic base stock, e.g., an ester. A lubricating engine oil comprising a lubricating oil base stock as a major component and an alkylated aromatic base stock as a minor component. The alkylated aromatic base stock is present in an amount sufficient for the lubricating oil to exhibit improved nitrile seal compatibility as compared to nitrile seal compatibility achieved using a lubricating oil containing a minor component other than the alkylated aromatic base stock.

Abstract: The invention relates to dispersions comprising I) at least one polymer that is effective for mineral oils as a cold extrusion improver and is soluble in oil, II) at least one organic solvent that cannot be mixed with water, III) water, IV) at least one alkanolamine salt of a polycyclic carboxylic acid as a dispersing agent, and V) possibly at least one organic solvent that can be mixed with water.

Abstract: Provided is an antioxidant composition, including: a compound (A) represented by the following general formula (1); and an amine-based antioxidant (B) and/or a phenol-based antioxidant (C) other than the compound (A): (wherein R represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and n represents a number from 1 to 3.

Abstract: Provided are lubricating engine oils including a lubricating oil base stock as a major component and an alkylated aromatic base stock as a minor component. One or more of engine wear and corrosion resistance are improved as compared to engine wear and corrosion resistance achieved using a lubricating oil containing a minor component other than the alkylated aromatic base stock, e.g., an ester having a D5293 viscosity of less than 10,000 cP at ?35° C. In an engine lubricated with the lubricating oil, one or more of engine wear and corrosion resistance are improved as compared to engine wear and corrosion resistance achieved using a lubricating oil containing a minor component other than the alkylated aromatic base stock, e.g., an ester having a D5293 viscosity of less than 10,000 cP at ?35° C. This improvement in engine wear and corrosion control means that engine oils can be formulated with very high saturate content base stocks such as PAOs or GTL stock while providing improved engine durability.

Abstract: The present invention relates to a method of lubricating a driveline device comprising supplying to the driveline device a lubricating composition comprising an oil of lubricating viscosity and an aromatic hydroxy-substituted compound. The invention further provides for the use of the lubricating composition comprising the aromatic hydroxy-substituted compound as at least one of a filterability aid, and a wax crystal growth modifier/gelation inhibitor in the driveline device.

Abstract: The invention relates to dispersions comprising I) at least one polymer that is effective for mineral oils as a cold extrusion improver and is soluble in oil, II) at least one organic solvent that cannot be mixed with water, III) water, IV) at least one alkanolamine salt of a polycyclic carboxylic acid as a dispersing agent, and V) possibly at least one organic solvent that can be mixed with water.

Abstract: Mineral oil distillates having an aromatics content of less than 21% by weight, a water content of less than 150 ppm and a conductivity of at least 50 pS/m, and comprising from 0.1 to 200 ppm of at least one alkylphenol-aldehyde resin (constituent I) which includes a structural element of the formula in which R5 is C1-C200-alkyl or C2-C200-alkenyl, O—R6 or O—C(O)—R6, R6 is C1-C200-alkyl or C2-C200-alkenyl and n is from 2 to 100, and from 0.1 to 200 ppm of at least one polar oil-soluble nitrogen compound (constituent II), excluding those mineral oil distillates in which between 0.001 and 10 ppm of an oil-soluble, organic sulfonic acid-ammonium salt are present.

Abstract: The invention relates to antioxidant compositions for lubricants and organic polymers comprising a first antioxidant comprising a reaction product of p-cresol, dicyclopentadiene and isobutylene; and a second antioxidant comprising a diarylamine. The first antioxidant preferably has the structure: wherein n is 0-50, and R1 and R2 are independently hydrogen, a straight or branched C1-C30 alkyl or alkylene group optionally substituted with one or more substituents, C3-C12 cycloalkyl, C5-C12 aryl, or C6-C12 alkylaryl. The second antioxidant preferably has the formula: (R3)a—Ar1—NH—Ar2—(R4)b wherein Ar1 and Ar2 are independently aromatic hydrocarbon groups and R3 and R4 are independently hydrogen or hydrocarbyl groups having from 6 to about 100 carbon atoms and a and b are independently 0 to 3 but (a+b) is not greater than 4.

Abstract: The present invention provides a grease composition or a lubricating oil composition which is capable of effectively preventing hydrogen brittleness-caused peeling from occurring on a rolling surface of a rolling bearing, is excellent in durability in a high temperature and speed operation, and can be used for a long time. A grease-packed bearing (1) has an inner ring (2), an outer ring (3), and a plurality of rolling elements (4). A sealing member (6) for sealing a grease composition (7) is provided at openings (8a) and (8b) disposed at both axial ends of the inner ring (2) and the outer ring (3). The grease composition (7) includes a base grease composed of a base oil and a thickener and an additive added to the base grease. The additive contains at least one compound selected from among plant-derived polyphenolic compounds and compounds formed by decomposition thereof.

Abstract: The present invention is directed to lubricating oils exhibiting improved resistance to oxidation and deposit/sludge formation comprising a lubricant base oil and catalytic antioxidants comprising an effective amount of a) one or more polymetal organometallic compound; and, b) effective amounts of one or more substituted N,N?-diaryl-o-phenylenediamine compounds or c) one or more hindered phenol compounds or both, to a method for improving the antioxidancy and the resistance to deposit/sludge formation of formulated lubricating oil compositions by the addition thereto of an effective amount of the aforementioned catalytic antioxidants, and to an additive concentrate containing the aforementioned catalytic antioxidants.

Abstract: Disclosed are a lubricant composition including a lubricating base oil, fine particles and a calcium sulfonate-based thickener, a speed reduction gear filled with the lubricant composition, and an electric power steering apparatus including the speed reduction gear. The invention reduces operating noise of the speed reduction gear, regardless of the amount of backlash that occurs on combining a small gear and a large gear and without a more complicated structure for the speed reduction gear, by action of the fine particles. Further, separation of oil is prevented, by action of the calcium sulfonate-based thickener of the lubricant composition, so that electric power steering apparatus noise within the inside of a car is reduced at a low cost.

Abstract: Liquid compositions containing a specific hindered phenol or a hindered phenol in combination with an aromatic phosphite are provided which are used as a thermal interface between a heatsink and a chip during a test procedure for electronic components which compositions enhance the thermal conductivity between the heatsink and the chip, are easily removed from the heatsink and the chip after the test procedure without any deleterious residue and which allow the use of high temperatures for extended periods during the test procedure without any significant degradation of the composition. A method for using the compositions in electronic component test procedures such as burn-in procedures is also provided.

Abstract: A lubricating oil composition for refrigerator is provided by adding base oil with biphenols selected from 4,4?-methylenebis(2,6-di-t-butyl-phenol), 2?2-methylenebis(4-methyl-6-t-butylphenol), 2,2?-methylenebis(4-ethyl-6-t-butylphenol) and 4,4?-butylidenebis(3-methyl-6-t-butylphenol).

Abstract: An oil-soluble hydrocarbyl phenol aldehyde condensate having the following structure: wherein n is 0 to 10, preferably 1 to 8, more preferably 2 to 6, and most preferably 3 to 5; Y is a divalent bridging group, and is preferably a hydrocarbyl group, preferably having from 1 to 4 carbon atoms; and R is a hydrocarbyl group having from 4 to 30, preferably 8 to 18, and most preferably 9 to 15 carbon atoms. The oil-soluble hydrocarbyl phenol aldehyde condensate has a weight average molecular weight (Mw) of 1250 to 1680, as measured by MALDI-TOF (Matrix Assisted Laser Desorption Ionization-Time of Flight) mass spectrometry.

Abstract: Lubricating oil additive concentrates containing oil of lubricating viscosity, at least one basic metal complex, an oil-soluble hydrocarbyl phenol aldehyde condensate, and an organic friction modifier containing at least one hydroxyl and/or amino group.

Abstract: A drag reducing additive for heavy oil, such as crude oil, includes a polymeric alkyl-substituted phenol formaldehyde resin and a solvent having at least one of an ester (e.g. ethyl acetate), an aldehyde (e.g. butyraldehyde), and an aromatic hydrocarbon (e.g. toluene, xylene, and the like), or mixtures thereof. When used together with a diluent (e.g. condensate, naphtha, or the like), the additive may reduce viscosity of the combined oil, diluent, and additive by at least 20%, increase throughput by at least 6%, reduce power consumption by at least 3%, reduce the diluent proportion by at least 3%, or some combination of these effects, as compared with an otherwise identical heavy oil without the additive.

Abstract: The present invention is directed to lubricating oils exhibiting improved resistance to oxidation and deposit/sludge formation comprising a lubricant base oil and catalytic antioxidants comprising an effective amount of a) one or more polymetal organometallic compound; and, b) effective amounts of one or more substituted N,N?-diaryl-o-phenylenediamine compounds or c) one or more hindered phenol compounds or both, to a method for improving the antioxidancy and the resistance to deposit/sludge formation of formulated lubricating oil compositions by the addition thereto of an effective amount of the aforementioned catalytic antioxidants, and to an additive concentrate containing the aforementioned catalytic antioxidants.

Abstract: Lubricant blends and finished gear oils comprising a lubricant base oil fraction derived from highly paraffinic wax, a petroleum derived base oil, and a pour point depressant are provided. The lubricant base oil fraction derived from highly paraffinic wax comprises less than 0.30 weight percent aromatics, greater than 5 weight percent molecules with cycloparaffinic functionality, and a ratio of weight percent of molecules with monocycloparaffinic functionality to weight percent of molecules with multicycloparaffinic functionality greater than 15. The petroleum derived base oils comprises greater than 90 weight percent saturates and less than 300 ppm sulfur and is preferably selected from the group consisting of a Group II base oil, a Group III base oil, and mixtures thereof. These lubricant blends have surprising low Brookfield viscosities at ?40° C.

Abstract: Use of an oil-soluble hydrocarbyl phenol aldehyde condensate as an antiwear additive in a lubricating oil composition. The oil-soluble hydrocarbyl phenol aldehyde condensate has the following structure: wherein n is 0 to 10, preferably 1 to 8, more preferably 2 to 6, and most preferably 3 to 5; Y is a divalent bridging group, and is preferably a hydrocarbyl group, preferably having from 1 to 4 carbon atoms; and R is a hydrocarbyl group having from 4 to 30, preferably 8 to 18, and most preferably 9 to 15 carbon atoms.

Abstract: Lubricant blends and finished gear oils comprising a Fischer-Tropsch derived lubricant base oil fraction, a petroleum derived base oil, and a pour point depressant are provided. The Fischer-Tropsch derived lubricant base oil fraction comprises less than 0.30 weight percent aromatics, greater than 5 weight percent molecules with cycloparaffinic functionality, and a ratio of weight percent of molecules with monocycloparaffinic functionality to weight percent of molecules with multicycloparaffinic functionality greater than 15. The petroleum derived base oils comprises greater than 90 weight percent saturates and less than 300 ppm sulfur and is preferably selected from the group consisting of a Group II base oil, a Group III base oil, and mixtures thereof. These lubricant blends have surprising low Brookfield viscosities at ?40° C.

Abstract: Quenching oil compositions comprising (1) an oil having kinematic viscosity (ASTM Test Method D-445) at 40° C. ranging from about 4 to about 45 mm2sec?1 (about 40 to about 210 Saybolt Universal Seconds (SUS)) and having a saturated content from about 80% to about 100%; and (2) an alkali metal salt of saligenin derivative and optionally, further comprising at least one of (3) an aliphatic polyolefin having Mn ranging from about 300 to about 10,000; (4) at least one member selected from the group consisting of metal salts of hydrocarbyl substituted phenols, salicylic acids, carboxylic acids, and sulfonic acids; and (5) at least one member selected from the group consisting of hydrocarbyl substituted succinic esters, amides, ester-amides, imides, amine salts, acid-esters, acid-amides ester-amine salts, amide-amine-salts and acid-amine salts, and methods of heat treating metals comprising employing said quenching oils.

Abstract: A lubricating oil composition having a total base number of more than 15 mg KOH/g, as determined by ASTM D2896, and including at least 40 mass % of an oil of lubricating viscosity; at least one detergent; and at least one compound of the formula (II): In formula (II), each Ar independently represents an aromatic moiety having 0 to 3 substituents selected from the group consisting of alkyl, alkoxy, alkoxyalkyl, hydroxy, hydroxyalkyl, acyloxy, acyloxyalkyl, aryloxy, aryloxy alkyl, halo and combinations thereof; each L is independently a linking moiety comprising a carbon-carbon single bond or a linking group; each Y? is independently a moiety of the formula Z(O(CR2)n)yX—, wherein X is selected from the group consisting of (CR?2)z, O and S; R and R? are each independently selected from H, C1 to C6 alkyl and aryl; z is 1 to 10; n is 0 to 10 when X is (CR?2)z, and 2 to 10 when X is O or S; y is 1 to 30; Z is H, an acyl group, an alkyl group or an aryl group; each a is independently 0 to 3, with the proviso tha

Abstract: Lubricating oils containing an additive formulation including at least one sulphonate, saligenin and salixarate detergent provide improved wear performance and decreased sulphur and phosphorus emissions.

Abstract: The invention relates to a process for preparing an overbased metal detergent in an oil medium comprising the steps of: (1) providing a metal salt selected from the group consisting of a hydrocarbyl-substituted organic acid; a hydrocarbyl-substituted phenol, a phenate, a hydrocarbyl-substituted carboxylate and mixtures thereof; (2) further providing methanol and a mixture of alcohols containing 2 to about 7 carbon atoms, wherein the mole ratio of methanol to the mixture of alcohols is about 2.

Abstract: Lubricating oil formulations comprising base oil, sulfur-phosphorous anti-wear/extreme pressure agents and hindered phenol antioxidants which anti-wear/extreme-pressure agents and hindered phenolic antioxidants are prone to crystal formation wherein the base oil is characterized as having a saturates content of less than 99% are stabilized against crystal formation by the addition of a minor amount of a high molecular weight di- or polycarboxylic acid anhydride, or mixture thereof.

Abstract: The invention relates to additives for improving the flowability of mineral oils, containing: A) 1-40 wt. % of at least one copolymer, which is oil-soluble and improves the cold flow properties of mineral oil, selected from A1) copolymers consisting of 80 to 96.5 mol % ethylene and 3.5-20 mol % vinyl esters of carboxylic acids with 1-20 C atoms and/or (meth)acrylic acid esters of alcohols with 1-8 C atoms, and A2) homopolymers or copolymers of esters, containing C10-C30 alkyl radicals, of ethylenically unsaturated carboxylic acids with up to 20 mol % of other olefinically unsaturated compounds, B) 20-80 wt. % of at least one poly-alpha-olefin with a molecular weight of 250-5000, derived from monoolefins with 3-5 C atoms, and C) 5-70 wt.

Abstract: This invention relates to a lubricating oil composition, comprising: (A) a base oil; and a phosphorus-containing compound represented by the formulae wherein in Formulae (B-I) and (B-II), R1, R2 and R3 are independently hydrogen or hydrocarbyl groups, and a, b and c are independently zero or 1; the lubricating oil composition being characterized by a sulfur content of about 0.01 to about 0.25% by weight.

Abstract: Lubricating oil compositions providing superior soot dispersing characteristics, which contain a combination of a high molecular weight dispersant and a soot dispersant comprising a linked aromatic oligomer.

Abstract: Lubricating oils containing an additive formulation including at least one sulphonate, saligenin and salixarate detergent provide improved wear performance and decreased sulphur and phosphorus emissions.

Abstract: Lubricating oil formulations comprising base oil, sulfur-phosphorous anti-wear/extreme pressure agent and hindered phenol antioxidant, which combination of extreme pressure agent and hindered phenol antioxidant produces crystals and containing antioxidants, wherein the base oil is characterized as having a saturates content of 99 wt % or more is stabilized against crystal formation by the addition of a minor amount of high molecular weigh di- or polycarboxylic acid, or anhydride and an ester.

Abstract: A composition comprises a sulphur- and phosphorus-free, boron-containing overbased metal salt of a calixarene. The boron-containing overbased calixarene is useful in a lubricant additive composition, a lubricant composition, and a method to lubricate an internal combustion engine. The boron-containing overbased calixarene advantageously provides detergent and antiwear performance and does so without increasing the sulphur or phosphorus content of a lubricant additive or lubricant composition.

Abstract: A lubricant containing (a) a synthetic base oil composition having an overall kinematic viscosity of at least about 4.8×10−6m2/s (4.8 cSt) at 100° C. and a viscosity index of at least about 110; (b) a dispersant-viscosity modifier; and (c) a sulfur-free functionalized hydrocarbyl-substituted phenol detergent provides improved valve train wear, with longer drain intervals, to heavy duty diesel engines.

Abstract: A low sulfate ash lubricating oil composition comprising an oil of lubricating viscosity, 0.1 to 3.0% of a calcium overbased acidic material, 0.1 to 2.0% of a magnesium overbased acidic material, and at least 0.5% of a combination of an alkylene-coupled hindered phenol antioxidant and an antioxidant other than an alkylene-coupled hindered phenol antioxidant, is particularly useful for lubricating stationary gas engines.

Abstract: A low sulfate ash lubricating oil composition comprising an oil of lubricating viscosity, 0.1 to 3.0% of a calcium overbased acidic material, 0.1 to 2.0% of a magnesium overbased acidic material, and at least 0.5% of a combination of an alkylene-coupled hindered phenol antioxidant and an antioxidant other than an alkylene-coupled hindered phenol antioxidant, is particularly useful for lubricating stationary gas engines.

Abstract: A composition of an antioxidant of the formula where R3 is an alkyl group of 2 to 6 carbon atoms, and a dispersant or a detergent, is a useful additive package for lubricant compositions.

Abstract: A lubricant containing (a) a synthetic base oil composition having an overall kinematic viscosity of at least about 4.8×10−6 m2/s (4.8 cSt) at 100° C. and a viscosity index of at least about 110; (b) a dispersant-viscosity modifier; and (c) a sulfur-free functionalized hydrocarbyl-substituted phenol detergent provides improved valve train wear, with longer drain intervals, to heavy duty diesel engines.

Abstract: This invention relates to a lubricating oil composition, comprising: (A) a base oil; and a phosphorus-containing compound represented by the formulae 1

Abstract: Hindered tert-butylphenolic antioxidant compositions characterized by a low level of volatile and undesirable single-ring tert-butylphenolic antioxidants and a high level of non-volatile multi-ring (or methylene bridged) tert-butylphenolic antioxidants are obtained by reacting a specific mixture of ultra pure ortho-tert-butylphenol (OTBP), ultra pure 2,6-di-tert-butylphenol (DTBP) and formaldehyde in a solvent in the presence of catalyst. These antioxidants are further characterized by having a low level of 2,6-di-tert-butylphenol, low levels of ortho-tert-butylphenol, and trace levels of 2,4,6-tri-tert-butylphenol.

Abstract: A composition of an antioxidant of the formula 1

Abstract: A lubricant containing (a) a synthetic base oil composition having an overall kinematic viscosity of at least about 4.8×10−6 m2/s (4.8 cSt) at 100° C. and a viscosity index of at least about 110; (b) a dispersant-viscosity modifier; and (c) a sulfur-free functionalized hydrocarbyl-substituted phenol detergent provides improved valve train wear, with longer drain intervals, to heavy duty diesel engines.

Abstract: A saligenin derivative such as the magnesium salt represented by the formula is useful as an additive for a lubricating composition. Preferably X is —CHO or —CH2OH, and Y is —CH2— or —CH2OCH2—. R1 is a hydrocarbyl group containing 1 to 60 carbon atoms and m is 0 to 10. At least one aromatic ring should contain an R1 substituent and the total number of carbon atoms in all R1 groups should be at least 7.

Abstract: This invention relates to a composition comprising at least one sulphur-containing calixarene represented by formula (I) or a metal salt of said calixarene, wherein in formula (I): Y is a divalent bridging group, at least one of said bridging groups being a sulphur atom; R3 is hydrogen, a hydrocarbyl or a hetero-substituted hydrocarbyl group; either R1 is hydroxyl and R2 and R4 are independently either hydrogen, hydrocarbyl or hetero-substituted hydrocarbyl, or R2 and R4 are hydroxyl and R1 is either hydrogen, hydrocarbyl or hetero-substituted hydrocarbyl; and n is a number having a value of at least 4. In one embodiment, the foregoing salt is an overbased salt. The invention also relates to additive compositions and finished lubricating oil compositions containing the foregoing overbased salt. The invention also relates to a process for making the foregoing overbased salt.

Abstract: There are disclosed fuel compositions containing an additive formed by admixture of (i) at least one ethylene polymer, (ii) the product of the condensation reaction between an aldehyde or ketone or reactive equivalent thereof and at least one compound comprising one or more aromatic moieties having at least one substituent of the formula XR1 and one further substituent R2 wherein X is oxygen of sulfur, R1 is hydrogen or a moiety bearing at least one hydrocarbyl group and R2 represents a hydrocarbyl group and (iii) at least one oil soluble polar nitrogen compound different from the condensation product and having one or more substituents of the formula NR13 where R13 represents a hydrocarbyl group containing 8 to 40 carbon atoms.

Abstract: An overbased metal salt of a sulphur-free calixarene having a substituent hydroxyl group or groups available for reaction with a metal base, the calixarene having a molecular weight of at least 1880.

Abstract: A lubricating oil composition for a wet clutch, particularly for an automatic transmission, which comprises mineral oil, synthetic oil or a mixture thereof as a base oil, and which contains 0.1 to 4.0% by weight of at least one compound selected from the group consisting of calcium sulfonate and calcium phenate, 0.1 to 0.5% by weight of zinc dithiophosphate, and 0.1 to 1.5% by weight of a bisphenol antioxidant, each based on the total weight of the lubricating oil composition. The composition has excellent initial anti-shudder properties, anti-shudder properties of long duration, and good thermal-oxidative stability.