Method for lubricating automotive or industrial gears

Abstract

The disclosed technology relates to an automotive or industrial gear oil for automotive or industrial gears and axles and bearings, the automotive or industrial gear oil containing an oil of lubricating viscosity, optionally a phosphate and / or thiophosphate compound, particularly a sulfurized olefin, and a metal thiophosphate compound such as zinc dialkyldithiophosphate, and a method of improving the operating efficiency and temperature of such automotive or industrial gears by lubricating them with the automotive or industrial gear oil.

Description

[Background technology]

[0001] The disclosed technology relates to lubricant compositions for automotive or industrial gears, and axles and bearings, the automotive or industrial gear oil containing an oil of lubricating viscosity, optionally a phosphate and / or thiophosphate compound, particularly a sulfurized olefin, and a metal thiophosphate compound such as zinc dialkyldithiophosphate, and to a method of improving the operating efficiency and temperature of such automotive or industrial gears by lubricating them with the automotive or industrial gear oil. Driveline power transmission devices (such as gears or transmissions) present very difficult engineering problems and solutions to meet multiple, often conflicting, lubrication requirements while providing durability and cleanliness.

[0002] Improving operational efficiency is a common goal shared by both original equipment manufacturers and lubricant manufacturers. Original equipment manufacturers sometimes focus on reducing surface roughness using mechanical processing methods to improve operational efficiency and reduce power losses. These mechanical processing methods include honing, top polishing, and vibratory finishing. Alternatively, lubricant manufacturers often aim to optimize viscosity and reduce fluid traction coefficients to optimize operational efficiency. Current mechanical processing methods can be expensive and time-consuming to implement in large-scale automotive gear production. Therefore, there is a desire to improve operational efficiency by modifying fluid properties rather than relying on mechanical processes to achieve this goal.

[0003] U.S. Patent No. 10,316,712, issued to Douglass et al. on June 11, 2019, teaches the use of various additives to reduce the roughness of additive products and maximize energy efficiency. The data in the '712 patent suggest that many different additives can function to reduce surface roughness, and indeed, even unadditivated lubricants can reduce surface roughness. The '712 patent does not teach how to provide any other benefits to the lubricant, such as providing the performance required by ASTM D7452, ASTM D6121, ASTM D4172, or ASTM D5704. While surface roughness and traction coefficient measurements are often used as predictive tools to understand lubricating fluid contributions to efficiency improvement, a more direct route to determining operating efficiency is to record the power loss of an electric motor driven axle efficiency rig as it undergoes a drive cycle. Rig testing is preferred over vehicle testing to improve reproducibility and repeatability. Operating efficiency is related to power loss by the formula: % efficiency = [(power input - power loss) / power input] * 100%. Efficiency or power loss can also be related to operating temperature, as reported in the following literature (Barton, W et al., "Impact of Viscosity Modifiers on Gear Oil Efficiency and Durability": Part II, SAE International 01-0299, 2013, pp. 295-309, doi:10.4271 / 2013-01-0299, US 8,435,932, US 6,303,547). Operating temperature is closely correlated with operating efficiency. Operating inefficiencies generate heat, resulting in higher operating temperatures. Therefore, the less heat generated in a more efficient system, the lower the operating temperatures observed. Lubricant solutions that can result in improved fluid efficiency by minimizing power losses and operating temperatures would be both technically and commercially advantageous. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] U.S. Patent No. 10,316,712 [Patent Document 2] U.S. Patent No. 8,435,932 [Patent Document 3] U.S. Patent No. 6,303,547 [Non-patent literature]

[0005] [Non-Patent Document 1] Barton, W et al., "Impact of Viscosity Modifiers on Gear Oil Efficiency and Durability": Part II, SAE International 01-0299, 2013, pp295-309, doi:10.4271 / 2013-01-0299 Summary of the Invention [Means for solving the problem]

[0006] The use of certain sulfurized olefin mixtures, along with metal alkyl thiophosphate and optionally amine alkyl (thio)phosphate chemistries not commonly used in gear oils, has been found to be surprisingly beneficial in minimizing power losses and reducing operating temperatures.

[0007] Accordingly, one aspect of the present technology is directed to an automotive or industrial gear oil comprising an oil of lubricating viscosity, 0.01 to 10 wt. % of a sulfurized olefin, and 0.1 to 2 wt. %, or 0.2 to 1.9 wt. %, or 0.2 to 1 wt. %, or 1.0 to 1.8 wt. % of a metal alkylthiophosphate. The lubricant may optionally include 0.5 to 2.0 wt. % of an amine alkyl(thio)phosphate compound.

[0008] The sulfurized olefin may be the reaction product of an olefin containing 2 to 6 carbon atoms reacted with hydrogen sulfide and sulfur at superatmospheric pressure in the presence of a catalyst. In one embodiment, the sulfurized olefin has the formula R1-S x-R2, where R1 and R2 are independently derived from olefins containing 2 to 6 carbon atoms, and x is an integer from 1 to 10, provided that the sulfurized olefin has a sulfur content of from about 10 to about 50 weight percent.

[0009] In embodiments, the amine alkylthiophosphate may be a dialkyldithiophosphate.

[0010] The metal alkylthiophosphate in the automotive or industrial gear oil may include a zinc dialkyldithiophosphate. In some embodiments, the zinc dialkyldithiophosphate may be a secondary zinc dialkyldithiophosphate.

[0011] In embodiments, the amine alkyl(thio)phosphate may simply be an amine alkyl phosphate. In other embodiments, the amine alkyl(thio)phosphate may be an amine alkyl thiophosphate. In further embodiments, the amine alkyl(thio)phosphate may include a combination of both an amine phosphate and an amine alkyl thiophosphate.

[0012] In one embodiment, the lubricant may include an amine phosphate that is a substantially sulfur-free alkyl phosphate amine salt having at least about 30 mole percent of phosphorus atoms in the alkyl pyrophosphate salt structure. In some embodiments, at least about 80 mole percent of the alkyl groups in such sulfur-free alkyl phosphates may be secondary alkyl groups of from about 3 to about 12 carbon atoms. In some embodiments, at least about 25 mole percent of the alkyl groups in such sulfur-free alkyl phosphates may be primary alkyl groups of from about 3 to about 12 carbon atoms.

[0013] The automotive or industrial gear oil may also contain other additives. In one embodiment, the automotive or industrial gear oil may contain other sulfur-containing additives in an amount to provide the composition with a total sulfur level of from about 0.75 to about 5 weight percent. In one embodiment, the automotive or industrial gear oil may have a total phosphorus level of from about 0.01 to about 0.5 weight percent.

[0014] Another aspect of the present technology includes a method of lubricating a driveline transmission, which may be, for example, an axle, a bearing, a transmission, or a gear, by supplying the driveline transmission with an automotive or industrial gear oil as described above and operating the driveline transmission. DETAILED DESCRIPTION OF THE INVENTION

[0015] Various preferred features and embodiments are described below by way of non-limiting example. One aspect of the present invention is an automotive or industrial gear oil containing (a) an oil of lubricating viscosity, (b) a sulfurized olefin or mixtures thereof, (c) a metal alkylthiophosphate, and optionally (d) at least one amine alkyl(thio)phosphate.

[0016] Oil of lubricating viscosity One component of the disclosed technology is an oil of lubricating viscosity, also referred to as a base oil. The base oil may be selected from any of the base oils in Groups I to V of the American Petroleum Institute (API) Base Oil Compatibility Guidelines (2011), namely: Base Oil Category Sulfur (%) Saturates (%) Viscosity Index Group I >0.03 and / or <90 80-120 Group II ≦0.03 and ≧90 80-120 Group III ≦0.03 and ≧90 >120 Group IV All Polyalphaolefins (PAO) Group V: All others not included in Groups I, II, III, or IV

[0017] Groups I, II, and III are mineral oil base stocks. Other commonly recognized base oil categories may be used, even if not officially identified by API. Group II+ refers to Group II materials with a viscosity index of 110-119 and lower volatility than other Group II oils, while Group III+ refers to Group III materials with a viscosity index of 130 or higher. Oils of lubricating viscosity may include natural or synthetic oils and mixtures thereof. Mixtures of mineral oils and synthetic oils, such as polyalphaolefin oils and / or polyester oils, may be used.

[0018] In one embodiment, the oil of lubricating viscosity is from 1.5 to 7.5, or from 2 to 7, or from 2.5 to 6.5, or from 3 to 6 mm 2 / sec at 100°C by ASTM D445. In one embodiment, the oil of lubricating viscosity comprises a polyalphaolefin having a kinematic viscosity at 100°C by ASTM D445 of 1.5 to 7.5, or any of the other aforementioned ranges.

[0019] Sulfurized Olefins The sulfurized olefins used in this technology encompass mixtures whose compositions are not easily described apart from the reactions used to prepare them. Generally, sulfurized olefins are about 80% polysulfides, mostly di-t-butyl polysulfides, with sulfur atoms ranging from 3 to 8. The mixtures have the formula: R1-S x -R2, where R1 and R2 are independently derived from an olefin containing 2 to 6 carbon atoms, and x is an integer from 1 to 10, provided that the sulfurized olefin has a sulfur content of from about 10 to about 50 weight percent.

[0020] More specifically, sulfurized olefins are the reaction products of olefins containing 2 to 6 carbon atoms reacted with hydrogen sulfide and sulfur under superatmospheric pressure in the presence of a catalyst.

[0021] The olefin compounds that can be sulfurized by the method of the present invention are diverse in nature and can be substituted or unsubstituted. When the olefin is substituted, the nature of the substituent is generally not a critical aspect of the technology; any such substituent is useful as long as it is compatible or compatible with the lubricating environment and does not interfere under the intended reaction conditions. Therefore, substituted compounds that are so unstable as to detrimentally decompose under the reaction conditions used are not considered. However, certain substituents, such as keto or aldehyde, can be desirably sulfurized. The selection of appropriate substituents is within the skill of the art or may be established through routine testing. Typical of such substituents are any of the moieties listed above, as well as hydroxy, amidine, amino, sulfonyl, sulfinyl, sulfonate, nitro, phosphate, phosphite, alkali metal mercapto, and the like.

[0022] Exemplary olefins from which sulfurized olefins can be prepared can contain 2 to 30 carbon atoms. In some cases, the olefin can contain 2 to 16 carbon atoms. In many cases, the olefin can contain 2 to 6 carbon atoms. The sulfurized olefins can be prepared from olefins containing 3 to 5 carbon atoms. The olefin can be butylene. The olefin can also be isobutylene. Amylene can be used as the olefin. The olefin can be isoamylene. The olefin can be diisobutylene. The sulfurized olefins suitable for use herein can be prepared from mixtures of any of the foregoing olefins.

[0023] The other two reagents essential to the process for preparing sulfurized olefins, sulfur and hydrogen sulfide, are well known and commercially available. Commercial sources of all of these reagents are commonly used, and impurities normally associated with them may be present without adverse effect.

[0024] The amounts of sulfur and hydrogen sulfide per mole of olefin compound are about 0.3 to 2.0 gram atoms and about 0.1 to 1.5 moles, respectively, with preferred ranges being about 0.5 to 1.5 gram atoms and about 0.4 to 1.25 moles, respectively, and most preferably about 0.7 to 1.2 gram atoms and about 0.4 to 0.8 moles, respectively.

[0025] The temperature range in which the sulfurization reaction is carried out is generally about 50-350°C. A preferred range is about 100-200°C, with about 125-180°C being particularly suitable. The reaction is carried out under superatmospheric pressure, which may be autogenous pressure (i.e., pressure that develops naturally during the course of the reaction), usually autogenous pressure, but may also be externally applied pressure. The exact pressure developed during the reaction depends on factors such as system design and operation, reaction temperature, and vapor pressures of the reactants and products, and may vary during the course of the reaction.

[0026] It is often advantageous to incorporate into the reaction mixture a material useful as a sulfurization catalyst. These materials may be acidic, basic, or neutral. Useful neutral and acidic materials include acidified clays such as "Super Filtrol," p-toluenesulfonic acid, dialkylphosphorodithioic acid, and phosphorus sulfides such as phosphorus pentasulfide. Preferred catalysts are basic materials. These may be inorganic oxides and salts such as sodium hydroxide, calcium oxide, and sodium sulfide. However, the most desirable basic catalysts are nitrogen bases, including ammonia and amines. Amines include primary, secondary, and tertiary hydrocarbyl amines, where the hydrocarbyl group is alkyl, aryl, aralkyl, alkaryl, or the like, and contains about 1 to 20 carbon atoms. Suitable amines include aniline, benzylamine, dibenzylamine, dodecylamine, naphthylamine, tallow amine, N-ethyldipropylamine, N-phenylbenzylamine, N,N-diethylbutylamine, m-toluidine, and 2,3-xylidine. Heterocyclic amines such as pyrrolidine, N-methylpyrrolidine, piperidine, pyridine, and quinoline are also useful.

[0027] Preferred basic catalysts include ammonia and primary, secondary, or tertiary alkylamines having about 1 to 8 carbon atoms in the alkyl group. Representative amines of this type are methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, di-n-butylamine, tri-n-butylamine, tri-sec-hexylamine, and tri-n-octylamine. Mixtures of these amines, as well as mixtures of ammonia and amines, can be used.

[0028] The amount of catalyst material used is generally about 0.05 to 2.0% by weight of the olefin compound, with about 0.0005 to 0.5 moles preferred and about 0.001 to 0.1 moles especially preferred for the preferred ammonia and amine catalysts per mole of olefin.

[0029] Because the exact chemical nature of sulfurized olefins is not known with certainty, it is most convenient to describe them in terms of their methods of preparation. However, when prepared from olefins containing fewer than seven carbon atoms, they appear to contain primarily disulfides, trisulfides, and tetrasulfides. The sulfur content of these sulfurized compositions is typically about 2-60 wt.%, preferably about 25-60 wt.%, and most desirably about 40-50 wt.%.

[0030] The aforementioned sulfurized olefins are known in the art and further details can be found, for example, in US Pat. No. 4,119,549, US Pat. No. 4,191,659 and US Pat. No. 4,344,854.

[0031] The aforementioned sulfurized olefins may be, for example, C4S, such as those prepared by the processes taught in U.S. Pat. Nos. 2,708,199 and 3,697,499. x (C4S y ) bThey are distinguished from C4 oligomeric polysulfides (b is 0-8, x and y are 1-3). Briefly, such oligomeric polysulfides are prepared by forming an adduct of 1-2 moles of an olefin and a sulfur halide, followed by reaction of the adduct with an alkali metal sulfide, optionally in the presence of free sulfur.

[0032] The amount of sulfurized olefin in an automotive or industrial gear oil may be 0.01 to 10 weight percent. The alternative amount of sulfurized olefin may be 0.1 to 8 weight percent, or 0.2 to 6 weight percent, or 0.5 to 5 weight percent. The amount of sulfurized olefin present may be suitable to provide a lubricant formulation with sulfur in an amount of 0.5 to 3 weight percent sulfur. This amount may be suitable to provide a lubricant formulation with 0.75 to 2.75 weight percent sulfur. This amount may be suitable to provide a lubricant formulation with 1 to 2.5 weight percent sulfur.

[0033] It will be understood by those skilled in the art that, like amine alkyl(thio)phosphates, sulfurized olefins typically comprise a mixture of various individual chemical species, and references herein to sulfurized olefins encompass mixtures of such compounds that may be prepared by the described syntheses.

[0034] Metal alkylthiophosphate compounds The automotive or industrial gear oil further comprises a metal alkylthiophosphate compound, which can be represented by the formula: [ka] In the formula, R 25 and R 26 are independently hydrogen, a hydrocarbyl group, or a mixture thereof, provided that R 25 and R 26At least one of R is a hydrocarbyl group, preferably alkyl or cycloalkyl (having 1 to 30, or 2 to 20, and in some cases 2 to 15 carbon atoms). 25 and R 26 can be a secondary alkyl group of 2 to 8 carbon atoms, or even 3 to 6 carbon atoms, such as those derived from 4-methylpentan-2-ol or isopropanol. 25 and R 26 can be a secondary alkyl group of 3 carbon atoms. In some embodiments, R 25 and R 26 can be a secondary alkyl group of 6 carbon atoms.

[0035] M is a metal and n is an integer equal to the available valence of M. M is a monovalent or divalent or trivalent, preferably a divalent, more preferably a divalent transition metal, most preferably zinc.

[0036] Examples of metal thiophosphates include zinc isopropyl methylamyl dithiophosphate, zinc isopropyl isooctyl dithiophosphate, zinc di(cyclohexyl)dithiophosphate, zinc isobutyl 2-ethylhexyl dithiophosphate, zinc isopropyl 2-ethylhexyl dithiophosphate, zinc isobutyl isoamyl dithiophosphate, zinc isopropyl n-butyl dithiophosphate, calcium di(hexyl)dithiophosphate, barium di(nonyl)dithiophosphate, zinc di(isobutyl)dithiophosphate, zinc isopropyl sec-butyl dithiophosphate, zinc isopropyl dithiophosphate, zinc isopropyl 4-methylpentan-2-ol dithiophosphate, zinc 4-methylpentan-2-ol dithiophosphate, or mixtures thereof.

[0037] The metal thiophosphate can be a zinc dialkyldithiophosphate. The zinc dialkyldithiophosphate can be designated as a primary zinc dialkyldithiophosphate or a secondary zinc dialkyldithiophosphate, depending on the structure of the alcohol used in its preparation. In some embodiments, the automotive or industrial gear oil can include a primary zinc dialkyldithiophosphate. In some embodiments, the automotive or industrial gear oil can include a secondary zinc dialkyldithiophosphate. In some embodiments, the automotive or industrial gear oil can include a mixture of primary and secondary zinc dialkylthiophosphates.

[0038] The metal from the metal alkylthiophosphate, such as zinc, can be provided at a concentration of about 0.02 to about 0.095 wt. % zinc, or about 0.025 to 0.085 wt. % zinc, or even about 0.03 to about 0.075 wt. % zinc. Such levels may be associated with metal alkylthiophosphate concentrations of about 0.15 to about 0.8 wt. %, about 0.2 to 0.75 wt. %, or even about 0.25 to about 0.70 wt. % zinc.

[0039] The metal from the metal alkylthiophosphate, such as zinc, can be provided at a concentration of about 0.02 to about 0.2 wt. % zinc, or about 0.025 to 0.19 wt. % zinc, or even about 0.03 to about 0.18 wt. % zinc. Such levels can be associated with a metal alkylthiophosphate concentration of about 0.2 to about 2 wt. % zinc, or about 0.25 to 1.9 wt. % zinc, or even about 0.3 to about 1.8 wt. % zinc.

[0040] In embodiments, the metal alkylthiophosphate may provide from 0.01 or 0.02 to about 0.095 weight percent phosphorus, or from about 0.025 to 0.085 weight percent, or even from about 0.03 to about 0.075 weight percent phosphorus.

[0041] In embodiments, the metal alkylthiophosphate may provide from 0.01 or 0.02 to about 0.2 weight percent phosphorus, or from about 0.025 to 0.19 weight percent, or even from about 0.03 to about 0.18 weight percent phosphorus.

[0042] Amine alkyl (thio) phosphate The lubricants of the disclosed technology will include at least one amine alkyl(thio)phosphate. As used herein, the inclusion of "thio" in parentheses means that the phosphate may or may not contain a sulfur atom.

[0043] In one embodiment, the amine alkyl (thio)phosphate can comprise an amine phosphate, i.e., a phosphate that is substantially free of sulfur. Substantially free of sulfur means that sulfur is not intentionally added to the amine phosphate, and preferably, the amine phosphate is completely free of sulfur. However, it is recognized that sulfur contamination may occur in production situations, resulting in some sulfur in the amine phosphate. To the extent that the amine phosphate contains some sulfur contamination, such contaminated compounds would still be considered substantially free of sulfur, provided that the sulfur does not affect the basic properties of the amine phosphate. Generally, the sulfur contamination level can be less than 2.5 wt%, or 1 wt%, or 0.1 wt%, or 0.01 wt% to be considered substantially free of sulfur.

[0044] In one embodiment, the amine phosphate may contain at least 30 mole percent of the phosphorus atoms in an alkyl pyrophosphate structure, as opposed to an orthophosphate (or monomeric phosphate) structure. The percentage of phosphorus atoms in the pyrophosphate structure may be 30-100 mole percent, or 40-90%, or 50-80%, or 55-70%, or 55-65%. The remaining amount of phosphorus atoms may be in the orthophosphate structure or may consist partially of unreacted phosphate or other phosphorus species. In one embodiment, up to 60 or up to 50 mole percent of the phosphorus atoms are in the mono- or di-alkyl-orthophosphate salt structure.

[0045] In one embodiment, the amine phosphate, such as present in the form of a pyrophosphate, may be represented in part by a semi-neutralized salt of formula (I) and / or a fully neutralized salt such as formula (II). [Table A]

[0046] The actual degree of neutralization of the amine phosphate, i.e., the degree of salting out of the -OH groups of the phosphorus ester, may be 50% to 100%, or 80% to 99%, or 90% to 98%, or 93% to 97%, or about 95%. Variants of these materials may exist, such as variants of formula (I) or formula (II), where the -OH group in formula (I) can be replaced by another -OR group. 1 or substituted with one or more -OR groups 1 The group may be replaced with an -OH group or R 1 The group may be a phosphorus-containing group (i.e., a terminal R 1 In place of the aryl group, a tertiary phosphorus structure is substituted. Exemplary variant structures may include: [Table B]

[0047] The structures of formulas (I) and (II) are shown as completely sulfur-free species in that the phosphorus atoms are bonded to oxygen atoms rather than sulfur atoms. However, it is possible that a small mole fraction of O atoms may be replaced by S atoms, such as 0-5 percent, or 0.1-4 percent, or 0.2-3 percent, or 0.5-2 percent.

[0048] Pyrophosphates can be distinguished from orthophosphates in general structure. [Table C] It may optionally also be present in the amounts described above.

[0049] The amine phosphates may also contain some amount of partial esters, including mono- and diesters of orthophosphate structure and diesters of pyrophosphate structure.

[0050] In formulas (I) and (II), each R 1 are independently alkyl groups of 3 to 12 carbon atoms. The alkyl groups can be primary or secondary groups, or a mixture of both primary and secondary groups. In certain embodiments, R 1 At least 80 mole percent, or at least 85, 90, 95, or 99 percent of the alkyl groups will be secondary alkyl groups. 1 At least 25 mole percent, or at least 30, 40, 50, 60, 70, 80, or 90, or even 99 mole percent of the alkyl groups will be primary alkyl groups.

[0051] In some embodiments, alkyl groups will have 3 or 4 to 12 carbon atoms, or 3 to 8, or 4 to 6, or 5 to 10, or 6 to 8 carbon atoms. Alkyl groups can be linear, branched, cyclic, or aromatic. Such groups include 2-butyl, 2-pentyl, 3-pentyl, 3-methyl-2-butyl, 2-hexyl, 3-hexyl, cyclohexyl, 4-methyl-2-pentyl, and other such secondary groups and their isomers (having 6, 7, 8, 9, 10, 11, or 12 carbon atoms), and propyl, butyl, isobutyl, pentyl, 3-methylbutyl, 2-methylbutyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, dodecyl, phenethyl, and other such primary groups and their isomers (having 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 carbon atoms). In some embodiments, the alkyl group will have a methyl branch at the -position of the group, an example of which is the 4-methyl-2-pentyl (also known as 4-methylpent-2-yl) group.

[0052] The amine alkyl(thio)phosphate may also be an amine alkylthiophosphate, where the alkylthiophosphate is represented by the formula (R'O)2PSSH, where each R' is independently a hydrocarbyl group containing from about 3 to about 30, preferably from about 3 to about 18, or from about 3 to about 12, or up to about 8 carbon atoms. Examples of R' groups include isopropyl, isobutyl, n-butyl, sec-butyl, various amyl, n-hexyl, methylisobutylcarbinyl, heptyl, 2-ethylhexyl, isooctyl, nonyl, behenyl, decyl, dodecyl, and tridecyl groups. Exemplary lower alkylphenyl R' groups include butylphenyl, amylphenyl, heptylphenyl, and the like. Examples of mixtures of R' groups include 1-butyl and 1-octyl; 1-pentyl and 2-ethyl-1-hexyl; isobutyl and n-hexyl; isobutyl and isoamyl; 2-propyl and 2-methyl-4-pentyl; isopropyl and sec-butyl; and isopropyl and isooctyl.

[0053] In one embodiment, the alkylthiophosphate of the amine alkylthiophosphate can be reacted with an epoxide or a polyhydric alcohol such as glycerol. This reaction product can be used alone or further reacted with a phosphate, anhydride, or lower ester. The epoxide is generally an aliphatic epoxide or styrene oxide. Examples of useful epoxides include ethylene oxide, propylene oxide, butene oxide, octene oxide, dodecene oxide, styrene oxide, and the like. Ethylene oxide and propylene oxide are preferred. The glycol can be an aliphatic glycol having 2 to about 12, or about 2 to about 6, or 2 or 3 carbon atoms. Glycols include ethylene glycol, propylene glycol, and the like. Alkylthiophosphates, glycols, epoxides, inorganic phosphorus reagents, and methods for reacting them are described in U.S. Pat. Nos. 3,197,405 and 3,544,465, the disclosures of which are incorporated herein by reference.

[0054] Amine component - The amine component of amine alkyl(thio)phosphate is R 2 3NH, wherein each R 2 are independently hydrogen or a hydrocarbyl group or an ester-containing group, or an ether-containing group, provided that at least one R 2 The group is a hydrocarbyl group or an ester- or ether-containing group (i.e., not NH3). Suitable hydrocarbyl amines include primary amines having 1 to 18 carbon atoms, or 3 to 12 or 4 to 10 carbon atoms, such as methylamine, ethylamine, propylamine, isopropylamine, butylamine and its isomers, pentylamine and its isomers, hexylamine and its isomers, heptylamine and its isomers, octylamine and its isomers (such as isooctylamine and 2-ethylhexylamine), and higher amines. Other primary amines include dodecylamine, fatty amines such as n-octylamine, n-decylamine, n-dodecylamine, n-tetradecylamine, n-hexadecylamine, n-octadecylamine, and oleylamine. Other useful fatty amines include commercially available fatty amines ("Armeen®" amines) (Akzo and Armeen® C, Armeen® O, Armeen® OL, Armeen® T, Armeen® HT, Armeen® S, and Armeen® SD), where the letter designation refers to the fatty group, such as coco, oleyl, tallow, or stearyl.

[0055] Secondary amines that can be used include dimethylamine, diethylamine, dipropylamine, dibutylamine, diamylamine, dihexylamine, diheptylamine, methylethylamine, ethylbutylamine, bis-2-ethylhexylamine, N-methyl-1-amino-cyclohexane, Armeen® 2C, and ethylamylamine. The secondary amine can be a cyclic amine such as piperidine, piperazine, and morpholine.

[0056] Suitable tertiary amines include tri-n-butylamine, tri-n-octylamine, tri-decylamine, tri-laurylamine, tri-hexadecylamine, and dimethyloleylamine (Armeen® DMOD). Triisodecylamine or tridecylamine and their isomers may be used.

[0057] Examples of mixtures of amines include (i) amines having 11 to 14 carbon atoms in the tertiary alkyl primary group, (ii) amines having 14 to 18 carbon atoms in the tertiary alkyl primary group, or (iii) amines having 18 to 22 carbon atoms in the tertiary alkyl primary group. Other examples of tertiary alkyl primary amines include tert-butylamine, tert-hexylamine, tert-octylamine (such as 1,1-dimethylhexylamine), tert-decylamine (such as 1,1-dimethyloctylamine), tert-dodecylamine, tert-tetradecylamine, tert-hexadecylamine, tert-octadecylamine, tert-tetracosanylamine, and tert-octacosanylamine. In one embodiment, useful mixtures of amines include "Primene® 81R" and "Primene® JMT," which (both manufactured and sold by Dow Chemical) may each be a mixture of C11-C14 tertiary alkyl primary amines and C18-C22 tertiary alkyl primary amines.

[0058] In other embodiments, the amine may be an ester-containing amine, such as an N-hydrocarbyl-substituted γ- or δ-amino(thio)ester, and is therefore a secondary amine. γδ ester-containing amines can be prepared, for example, by the Michael addition of a primary amine, typically having a branched hydrocarbyl group, with an ethylenically unsaturated ester or thioester, or by reductive amination of an ester of a 5-oxy-substituted carboxylic acid or thiocarboxylic acid. They can also be prepared by amination of an ester of a 5-halogen-substituted carboxylic acid or thiocarboxylic acid, or by reductive amination of an ester of a 2-amino-substituted hexanedioic acid, or by alkylation of an ester of a 2-aminohexanedioic acid.

[0059] The amine, whatever its type, reacts to neutralize the acidic groups of the phosphorus ester component to prepare an amine alkyl(thio)phosphate.

[0060] In one embodiment, the amine alkyl(thio)phosphate can be a phosphate amine of formula (I) or (II), or a variant thereof, wherein the amine is 2-ethylhexylamine.

[0061] In one embodiment, the amine alkyl(thio)phosphate can be an amine phosphate of formula (I) or (II), or a variant thereof, wherein the amine is an N-hydrocarbyl substituted γ- or δ-amino(thio)ester.

[0062] In one embodiment, the amine alkyl(thio)phosphate can be an amine alkylthiophosphate, which is 14 ~C 18 Alkylated dithiophosphates and C 11 ~C 14 It is a reaction product with Primene 81R™ (manufactured and sold by Dow), a mixture of tertiary alkyl primary amines.

[0063] In embodiments, the amine alkyl(thio)phosphates include combinations of amine phosphates, combinations of amine alkylthiophosphates, and combinations of amine phosphates and amine alkylthiophosphates.

[0064] The amount of amine alkyl (thio)phosphate in the automotive or industrial gear oil may be 0.01 to 5 weight percent. Alternative amounts of amine alkyl (thio)phosphate may be 0.2 to 3 weight percent, or 0.6 to 2 weight percent, or even 0.7 to 1.75 weight percent, or 0.2 to 1.2 weight percent, or 0.5 to 2.0 weight percent, or 0.55 to 1.4 weight percent, or 0.6 to 1.3 weight percent, or 0.7 to 1.2, or 1 to 2, or even 1.5 to 2, or 1.2 to 1.8 weight percent, or even 1.8 to 2.2 weight percent. This amount may be suitable to provide phosphorus to the lubricant formulation in an amount of 200 to 3000 ppm by weight, or 400 to 2000 ppm, or 300 to 2000, or 600 to 1500 ppm, or 700 to 1100 ppm, or 900 to 1900, or 1100 to 1800 ppm, or 1200 to 1600 ppm, or 1500 to 2000 ppm.

[0065] It will be understood by those skilled in the art that amine alkyl(thio)phosphates will typically comprise mixtures of various individual species, and it will be understood by those skilled in the art that reference herein to amine alkyl(thio)phosphates encompasses mixtures of such compounds that may be prepared by the described syntheses.

[0066] Other additives Automotive or industrial gear oils may also contain thiadiazoles and thiadiazole adducts, such as aftertreatment dispersants. Examples of thiadiazoles include 2,5-dimercapto-1,3,4-thiadiazole or oligomers thereof, hydrocarbyl-substituted 2,5-dimercapto-1,3,4-thiadiazoles, and hydrocarbylthio-substituted 2,5-dimercapto-1,3,4-thiadiazoles or oligomers thereof. Oligomers of hydrocarbyl-substituted 2,5-dimercapto-1,3,4-thiadiazoles are typically formed by forming sulfur-sulfur bonds between 2,5-dimercapto-1,3,4-thiadiazole units to form two or more oligomers of the thiadiazole unit. Further examples of thiadiazole compounds can be found in WO 2008 / 094759, paragraphs 0088-0090. The thiadiazole may be included at a concentration of from about 0.01 to about 2% by weight, or from about 0.05 to about 1.5% by weight, or even from 0.1 to about 1% by weight.

[0067] Other materials may be present in their conventional amounts in automotive or industrial gear oils, including, for example, viscosity modifiers, dispersants, pour point additives, extreme pressure agents, antifoam agents, copper corrosion inhibitors (such as dimercaptothiadiazole compounds), iron corrosion inhibitors, friction modifiers, dyes, fragrances, optionally detergents and antioxidants, and color stabilizers.

[0068] As used herein, automotive or industrial gear oil refers to an automotive or industrial gear oil having a level of additives sufficient to lubricate industrial gears or driveline power transmission devices, including automotive gears such as gears, bearings, or axles, or transmissions. In this regard, automotive or industrial gear oils can be distinguished from other lubricants, such as engine oil lubricants, based on their sulfur and phosphorus levels. Automotive or industrial gear oils can have a total sulfur level of about 0.75 to about 5 wt. %, based on the weight of the automotive or industrial gear oil. In some embodiments, the total sulfur level can be about 0.8 to about 4 wt. %, or even about 0.9 to about 3.5 wt. %, or about 1 to about 3 wt. %.

[0069] Automotive or industrial gear oils may also have total phosphorus levels of from about 0.01 to about 0.5 weight percent, or from 0.03 to about 0.35 weight percent, or even from about 0.05 to about 0.3 weight percent.

[0070] Phosphorus can be introduced into automotive or industrial gear oils from, for example, the amine alkyl (thio)phosphates described above, or other phosphorus-containing compounds. Such other phosphorus-containing compounds can include, for example, phosphites or phosphonates. Suitable phosphites or phosphonates include those having at least one hydrocarbyl group with 3 or 4 or more, or 8 or more, or 12 or more carbon atoms. The phosphites can be mono-, di-, or trihydrocarbyl-substituted phosphites. The phosphonates can be mono-, di-, or trihydrocarbyl-substituted phosphonates.

[0071] In one embodiment, the phosphite does not contain sulfur, i.e., the phosphite is not a thiophosphite.

[0072] The phosphite or phosphonate may be represented by the formula: [ka] wherein at least one R can be a hydrocarbyl group containing at least three carbon atoms, and the other R groups can be hydrogen. In one embodiment, two of the R groups are hydrocarbyl groups and the third is hydrogen. In one embodiment, each R group is a hydrocarbyl group, i.e., the phosphite is a trihydrocarbyl-substituted phosphite. The hydrocarbyl groups can be alkyl, cycloalkyl, aryl, acyclic, or mixtures thereof.

[0073] In the art, phosphonates (i.e., Formula XI with R = hydrocarbyl) are sometimes referred to as phosphite esters. When one of the R groups in Formula XII is an H group, the compound is generally considered a phosphite, although such compounds can often exist between the tautomers of Formulas XI and XII and therefore may also be referred to as phosphonates or phosphite esters. For ease of reference, the term phosphite as used herein will be considered to encompass both phosphites and phosphonates.

[0074] The R hydrocarbyl group can be straight-chained or branched, typically straight-chained, and saturated or unsaturated, typically saturated.

[0075] In one embodiment, the other phosphorus-containing compound is C 3~8 The compound may be a hydrocarbyl phosphite, a hydrocarbyl phosphite, or a mixture thereof, i.e., each R may independently be hydrogen or a hydrocarbyl group having 3 to 8 or 4 to 6 carbon atoms, typically 4 carbon atoms. 3~8 Hydrocarbyl phosphites include dibutyl phosphate.

[0076] In one embodiment, the phosphorus-containing compound is C 12~22 The phosphate group may be a hydrocarbyl phosphite, a phosphate group ... 12~22 Hydrocarbyl phosphites are C 16~18 Contains hydrocarbyl phosphites. 3 , R 4 , and R 5 Examples of alkyl groups include octyl, 2-ethylhexyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, octadecyl, octadecenyl, nonadecyl, eicosyl, or mixtures thereof. 12~22The hydrocarbyl phosphite may be present in the automotive or industrial gear oil from about 0.05% to about 4.0%, or from about 0.05% to about 3%, or from about 0.05% to about 1.5%, or from about 0.05% to about 1%, or from about 0.1% to about 0.5% by weight of the automotive or industrial gear oil.

[0077] In some embodiments, the other phosphorus-containing compound is C 3~8 and C 12 ~C 24 The present invention may include both hydrocarbyl phosphites and hydrocarbyl phosphites.

[0078] In one embodiment, the phosphate ester comprises the reaction product of (a) a monomeric phosphate or ester thereof and (b) at least two alkylene diols, the first alkylene diol (i) having two hydroxy groups in a 1,4 or 1,5 or 1,6 relationship, and the second alkylene diol (ii) being an alkyl-substituted 1,3-propylene glycol.

[0079] The sulfur-containing phosphite may be, for example, a compound represented by the formula [R 1 O(OR 2 )(S)PSC2H4(C)(O)OR 4 O] n P(OR 5 ) 2-n (O)H, (wherein, R 1 and R 2 are each independently a hydrocarbyl group having 3 to 12 carbon atoms or 6 to 8 carbon atoms, or R 1 and R 2 forms a ring containing 2 to 6 carbon atoms together with the adjacent O and P atoms, and R 4 is an alkylene group having 2 to 6 carbon atoms or 2 to 4 carbon atoms, and R 5 is hydrogen or a hydrocarbyl group having 1 to about 12 carbon atoms, and n is 1 or 2. 12~22The hydrocarbyl phosphite may be present in the automotive or industrial gear oil from about 0.05% to about 1.5% by weight of the automotive or industrial gear oil, or from about 0.1% to about 1.0% by weight of the automotive or industrial gear oil.

[0080] In one embodiment, the other phosphorus-containing compound may be a phosphorus-containing amide. The phosphorus-containing amide may be prepared by reacting a dithiophosphate with an unsaturated amide. Examples of unsaturated amides include acrylamide, N,N'-methylenebisacrylamide, methacrylamide, crotonamide, and the like. The reaction product of the phosphate with the unsaturated amide may be further reacted with a linking or coupling compound such as formaldehyde or paraformaldehyde. Phosphorus-containing amides are known in the art and are disclosed in U.S. Patent Nos. 4,670,169, 4,770,807, and 4,876,374, which are incorporated by reference for their disclosure of phosphorus amides and their preparation.

[0081] Automotive or industrial gear oils can also contain rust inhibitors. Rust inhibitors include organic compounds having one or more of an amine group, an ether group, a hydroxyl group, a carboxylic acid, an ester, or a base, or a nitrogen-containing heterocyclic group. Examples include fatty amines such as oleylamine, hydroxyamines such as isopropanolamine, condensates of hydroxyamines with fatty acids (such as the product of tall oil fatty acid with diethanolamine or N-hydroxyethylethylenediamine), carboxylic acids, esters, and salts (such as alkyl-substituted succinic acids, esters, and amine or ammonium salts, e.g., mono- or diesters from succinic acid and propylene oxide), and compounds with multiple functions. Examples of the latter include sarcosine derivatives with amide and acid functional groups (e.g., R 1 CO-NR 2-CH2-COOH). Materials with nitrogen-containing heterocycles include triazole compounds, such as tolyltriazole and triazine salts. Other rust inhibitors include ethoxylated phenols. Other rust inhibitors include various oxides that may be formed by partial oxidation of waxes or oils. Examples include paraffin oil oxides, wax oxides, and petroleum oxides. Other rust inhibitors include organoboron compounds, such as long-chain alkenyl amidoborates. Still others include alkali metal sulfonates, such as sodium sulfonate and sodium alkylbenzene sulfonate.

[0082] Other rust inhibitors include esters of hydroxy acids such as tartaric acid, citric acid, malic acid, lactic acid, oxalic acid, glycolic acid, hydroxypropionic acid, and hydroxyglutaric acid. 6~12 or C 6~10 or C 8~10 Esters including tartrate esters (i.e., especially diesters) formed from alcohols, such as isotridecyl tartrate, 2-ethylhexyl tartrate, and C 12~14 Linear Alcohol / C 13 Included are mixed tartrate esters of branched alcohols (e.g., 80-95:20-5 or 90:10 ratios). Amides and imides of such materials may also be useful.

[0083] Still other rust inhibitors include polyethers. These include polyalkylene oxides such as polyethylene oxide, polypropylene oxide, and copolymers of ethylene oxide and propylene oxide. Such polyethers may be end-capped with an alkyl group, such as a butyl group. Materials of this type are commercially available and are considered to be butyl-capped polypropylene oxide or butyl-capped ethylene oxide-propylene oxide copolymers. Such materials may also be referred to as polyether alcohols or polyether polyols when they contain a hydroxy group at one end of the chain.

[0084] In one embodiment, the rust inhibitor can be a polyether, while in other embodiments, the rust inhibitor can be one or more of an aliphatic amine, a condensate of a hydroxyamine and a fatty acid, a carboxylic acid, an ester, or a salt, a sarcosine derivative, a triazole compound, an ethoxylated phenol, a partially oxidized wax or oil, a long-chain alkenyl amidoborate, an ester of a hydroxy acid, or a sodium sulfonate.

[0085] The rust inhibitor may be present at 0.02 to 2 weight percent of the automotive or industrial gear oil, and in alternative embodiments, 0.05 to 1 weight percent or 0.1 to 0.5 weight percent or 0.1 to 0.2 weight percent.

[0086] The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 2 to 25 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 2 to 15 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 2 to 12 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 2 to 9 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 2 to 7 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 2 to 6 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 2 to 5 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 3 to 6.5 cSt. The automotive or industrial gear oil may have a kinematic viscosity at 100°C according to ASTM D445 of 3 to 5.5 cSt.

[0087] The disclosed technology generally provides a method for minimizing power losses and reducing operating temperatures in an automotive or industrial gear by providing an automotive or industrial gear oil to the automotive or industrial gear and operating the automotive or industrial gear.

[0088] This technology also provides a method for improving the operating efficiency of gears by lubricating the gears with an automotive or industrial gear oil and operating the gears. In particular, this technology provides a method for improving the operating efficiency of new gears by lubricating the gears with an automotive or industrial gear oil and operating the gears. By "new gears" is meant gears that have not previously been used in operation. Efficiency improvements can also be achieved in used gears that have previously operated under fluids other than the compositions taught herein.

[0089] In particular, the disclosed technology provides a method of lubricating a driveline power transmission device, comprising: supplying to the driveline power transmission device an automotive or industrial gear oil described herein, i.e., an automotive or industrial gear oil comprising (a) an oil of lubricating viscosity, (b) a sulfurized olefin described herein, and (c) a metal alkylthiophosphate, or, in some cases, (a) an oil of lubricating viscosity, (b) a sulfurized olefin described herein, (c) a metal alkylthiophosphate, and (d) an amine alkyl(thio)phosphate, and operating the driveline power transmission device for a period of time sufficient for the automotive or industrial gear oil to minimize power losses and reduce operating temperatures of the driveline power transmission device in a controlled manner to a greater extent than conventional gear lubricants, where this reduction in power losses can be measured during operation of the device using the automotive or industrial gear oil.

[0090] A driveline transmission may include at least two gears, such as in a vehicle gearbox (e.g., a manual transmission), or an axle or differential, or other driveline transmission. The driveline transmission may include a bearing. The rolling elements of the bearing may be cylindrical or ball in design. The lubricated gears may include an annular, spiral bevel, or more commonly, hypoid gears, such as those found in drive axles. The axle gear ratio may be between 2:1 and 8:1, and the ring gear diameter may be approximately 13 to 64 centimeters. The axle may incorporate an open differential or some type of traction enabler. The axle may be part of a drivetrain with one or more drive axles, such as a tandem or tridem design, and the axles may be coupled with a power splitter. Applications for these axles include light-, medium-, and heavy-duty vehicles (e.g., vocational or linehaul service) and may be used on highways or on public roads. The axles may be from a conventional petrol-powered vehicle, an electric-powered vehicle, or a hybrid of both. An electric axle may combine an electric motor, power electronics, and transmission in a unit that directly powers the vehicle's axles.

[0091] The lubricant should be able to meet other expected aspects of a lubricant during normal operation of the driveline power transmission.

[0092] As used herein, the term "condensation product" is intended to encompass esters, amides, imides, and other such materials that can be prepared by the condensation reaction of an acid or a reactive equivalent of an acid (e.g., an acid halide, anhydride, or ester) with an alcohol or an amine, regardless of whether the condensation reaction is actually carried out to lead to the product directly. Thus, for example, a particular ester may be prepared by a transesterification reaction rather than by a direct condensation reaction. The resulting product is still considered a condensation product.

[0093] The amounts of each chemical component listed are exclusive of any solvents or diluent oils that may normally be present in commercially available materials, i.e., on an active chemical basis, unless otherwise indicated. However, unless otherwise indicated, each chemical or composition referred to herein should be construed as a commercial material, which may contain isomers, by-products, derivatives, and other materials normally understood to be present in articles of commerce.

[0094] As used herein, the term "hydrocarbyl substituent" or "hydrocarbyl group" is used in its ordinary sense, which is well known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character. Examples of hydrocarbyl groups include: hydrocarbon substituents, i.e., aliphatic (e.g., alkyl or alkenyl groups), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic, aliphatic, and alicyclic-substituted aromatic substituents, as well as cyclic substituents in which the ring is completed through another portion of the molecule (e.g., two substituents together form a ring); Substituted hydrocarbon substituents, i.e., substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon character of the substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy groups); Hetero substituents, i.e., in the context of this invention, include substituents that have predominantly hydrocarbon character but contain other atoms in the ring or chain that is otherwise composed of carbon atoms, and substituents such as pyridyl, furyl, thienyl, and imidazolyl groups. Heteroatoms include sulfur, oxygen, and nitrogen. Generally, there are no more than two or no more than one non-hydrocarbon substituent for every 10 carbon atoms in the hydrocarbyl group; alternatively, the hydrocarbyl group may have no non-hydrocarbon substituents.

[0095] It is known that some of the substances described herein may interact in the final formulation, so the components of the final formulation may differ from those initially added. For example, metal ions (e.g., of a detergent) may migrate to other acidic or anionic sites on other molecules. The products formed thereby, including products formed by using the compositions of the present invention in their intended use, may not be easily described. Nevertheless, all such modifications and reaction products are within the scope of the present invention, and the present invention includes compositions prepared by mixing the above-described components.

[0096] The invention herein may be better understood with reference to the following examples. [Example]

[0097] A series of fully formulated automotive gear oils were prepared according to the formulations in Tables 1 and 2 below. [Table 1]

[0098] Samples 1 and 2 are identical except for the sulfurized olefin present. Sample 1 contains sulfurized olefin A, and Sample 2 contains sulfurized olefin B. Samples 3 and 4 are also identical except for the sulfurized olefin present. These samples differ from Samples 1 and 2 in that they each contain reduced levels of sulfurized olefin supplemented by the addition of zinc dialkyldithiophosphate.

[0099] Sulfurized olefin A is an oligomeric polysulfide.

[0100] Sulfurized Olefin B is sulfurized isobutylene according to the present technology.

[0101] Table 2 is very similar to Table 1 and presents recipes for four additional fluids. These samples are comparable to Samples 1-4, but all contain different sources of phosphorus amine salt. The phosphorus amine salt present in Samples 1-4 contains sulfur, while the phosphorus amine salt in Samples 5-8 is substantially free of sulfur. Additionally, each fluid contains either sulfurized olefin A or sulfurized olefin B, with or without zinc dialkyldithiophosphate. [Table 2]

[0102] Axle efficiency testing was completed for each fluid according to the following guidelines and procedures.

[0103] The axles used were commercially available and purchased from a North American tier 1 supplier with a 24-centimeter ring gear, open differential, and a 3.42:1 gear ratio. Each efficiency test was performed using a new axle and without temperature control. Temperatures were allowed to self-stabilize over time, and the axles were tested across the full operating window of the vehicle's intended speed and load. Table 3 shows speed-load maps representing 16 sets of conditions mimicking low, medium, medium-high, and high speeds from 500 to 2000 rpm, and pinion forces ranging from 100 to 500 Nm, representing various low, medium-low, medium, medium-high, and high loads likely to be encountered in urban and highway driving. [Table 3]

[0104] Tests were performed sequentially through stages 1 through 16. One complete cycle consisted of one full run of all 16 stages. The test was repeated for 10 cycles. Power loss and fluid temperature were measured and recorded after each stage. The power loss and temperature data reported here are from stages 7, 11, and 16 of the procedure. These stages exposed the fluids to a variety of operating conditions at moderate to high loads and speeds. Stage 16, the highest-power stage, exhibited the greatest differences in power loss and operating temperature, more dramatically than the other stages, but differences were also evident at lower loads and speeds. Data from cycles 1, 3, and 10 are reported for each fluid. Because each test was performed on a new axle, selected tests were performed two or three times at designated locations to reduce the variability inherent in the tests. Minimizing both power loss and operating temperature is paramount. [Table 4-1] [Table 4-2] [Table 4-3]

[0105] In the absence of ZDDP, Samples 1 and 2 show no significant difference between fluids containing either sulfurized olefin A or sulfurized olefin B. However, when ZDDP is present in the fluid, there is a much greater difference in the performance of Samples 3 and 4. Sample 4, which contains both ZDDP and sulfurized olefin B, exhibits the lowest power loss and the lowest operating temperature. [Table 5-1] [Table 5-2] [Table 5-3]

[0106] Comparing the results for Samples 5 and 6 containing different sulfurized olefins in the absence of ZDDP, little difference in performance is seen (Sample 5 contains sulfurized olefin A, and Sample 6 contains sulfurized olefin B). However, in the presence of ZDDP, the fluid containing sulfurized olefin B (Sample 8) shows clear performance improvement compared to the fluid containing sulfurized olefin A (Sample 7), and an improvement over Samples 5 and 6 which do not contain ZDDP.

[0107] In both data sets, when only sulfurized olefin A or B is used as the extreme pressure (EP) agent, power loss and operating temperatures are similar, regardless of the phosphorus-based antiwear additive. However, when zinc dialkyldithiophosphate is introduced as part of the EP system, sulfurized olefin B is substantially differentiated from sulfurized olefin A.

[0108] Additional efficiency tests were performed with a liquid formulated with the following ingredients: [Table 6]

[0109] The liquid contained a mixture of two phosphorus amine salts with varying levels of sulfurized olefin and zinc dialkyldithiophosphate. [Table 7-1] [Table 7-2] [Table 7-3]

[0110] The results for Sample 9 show comparable performance to Samples 4 and 8. With increasing levels of sulfurized olefin B and decreasing levels of ZDDP, the desirable reduction in power loss and operating temperature is still evident.

[0111] Each of the documents referenced above is incorporated herein by reference, including any prior application to which priority is claimed, whether or not specifically listed above. The reference to any document is not an admission that such document qualifies as prior art or constitutes general knowledge of one of ordinary skill in the art in any jurisdiction. Except in the examples or where expressly indicated, all numerical values ​​herein specifying amounts of ingredients, reaction conditions, molecular weights, numbers of carbon atoms, and the like are understood to be optionally modified by the word "about." It is understood that the upper and lower amount, range, and ratio limits set forth herein may be independently combined. Similarly, the ranges and amounts of each element of the invention may be used together with ranges or amounts of any other element.

[0112] As used herein, the transitional phrase "comprising," which is synonymous with "including," "containing," or "characterized by," is inclusive or open-ended and does not exclude additional, unrecited elements or method steps. However, within each "comprising" recitation herein, the term is intended to encompass, as alternative embodiments, the phrases "consisting essentially of" and "consisting of," where "consisting" excludes any unspecified element or step, and "consisting essentially of" permits the inclusion of additional, unrecited elements or steps that do not materially affect the essential or basic and novel characteristics of the composition or method under consideration. The phrases "consisting of" or "essentially consisting of," when applied to a claim element, are intended to limit all species of the type represented by that element, notwithstanding the absence of "comprising" anywhere in the claim.

[0113] a) an oil of lubricating viscosity and b) an oil of formula R1-S x1. An automotive or industrial gear oil comprising: c) 0.01 to 10 weight percent of a sulfurized olefin comprising a mixture of sulfurized olefins of formula -R2, wherein R1 and R2 are individually derived from olefins containing 2 to 6 carbon atoms, and x is an integer from 1 to 10, provided that the sulfurized olefin has a sulfur content of about 10 to about 50 weight percent; and c) 0.1 to 2 weight percent of a metal alkylthiophosphate.

[0114] The automotive or industrial gear oil of any one of the preceding sentences, wherein the oil of lubricating viscosity comprises a Group I oil.

[0115] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the oil of lubricating viscosity comprises a Group II oil.

[0116] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the oil of lubricating viscosity comprises a Group III oil.

[0117] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the oil of lubricating viscosity includes a Group III+ oil.

[0118] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the oil of lubricating viscosity includes a Group IV oil.

[0119] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the oil of lubricating viscosity includes a Group V oil.

[0120] The lubricating viscosity of the oil is 1.5 to 7.5 mm at 100°C according to ASTM D445. 2 1. The automotive or industrial gear oil of any one of the preceding sentences having a kinematic viscosity of 1 / 2 s.

[0121] Oil of lubricating viscosity is 2-7mm at 100°C according to ASTM D445 2 1. The automotive or industrial gear oil of any one of the preceding sentences having a kinematic viscosity of 1 / 2 s.

[0122] The lubricating viscosity of the oil is 2.5 to 6.5 mm at 100°C according to ASTM D445. 2 1. The automotive or industrial gear oil of any one of the preceding sentences having a kinematic viscosity of 1 / 2 s.

[0123] Oil of lubricating viscosity is 3-6 mm at 100°C according to ASTM D445 2 1. The automotive or industrial gear oil of any one of the preceding sentences having a kinematic viscosity of 1 / 2 s.

[0124] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the oil of lubricating viscosity comprises a polyalphaolefin.

[0125] The automotive or industrial gear oil of any one of the preceding sentences, wherein R1 and R2 of the sulfurized olefin are independently derived from an olefin containing 3 to 5 carbon atoms.

[0126] The automotive or industrial gear oil of any one of the preceding sentences, wherein at least one of R1 and R2 of the sulfurized olefin is independently derived from butylene.

[0127] The automotive or industrial gear oil of any one of the preceding sentences, wherein at least one of R1 and R2 of the sulfurized olefin is independently derived from isobutylene.

[0128] The automotive or industrial gear oil of any one of the preceding sentences, wherein at least one of R1 and R2 of the sulfurized olefin is independently derived from amylene.

[0129] The automotive or industrial gear oil of any one of the preceding sentences, wherein at least one of R1 and R2 of the sulfurized olefin is independently derived from isoamylene.

[0130] The automotive or industrial gear oil of any one of the preceding sentences, wherein at least one of R1 and R2 of the sulfurized olefin is independently derived from diisobutylene.

[0131] The automotive or industrial gear oil of any one of the preceding sentences, wherein at least one of R1 and R2 of the sulfurized olefin is derived separately from a mixture of any of the foregoing olefins.

[0132] The automotive or industrial gear oil of any one of the preceding sentences, wherein the amount of sulfur and hydrogen sulfide per mole of olefin compound in the sulfurized olefin is about 0.3 to 2.0 gram-atoms and about 0.1 to 1.5 moles, respectively.

[0133] The automotive or industrial gear oil of any one of the preceding sentences, wherein the amount of sulfur and hydrogen sulfide per mole of olefin compound in the sulfurized olefin is about 0.5 to 1.5 gram-atoms and about 0.4 to 1.25 moles, respectively.

[0134] The automotive or industrial gear oil of any one of the preceding sentences, wherein the amount of sulfur and hydrogen sulfide per mole of olefin compound in the sulfurized olefin is about 0.7 to 1.2 gram-atoms and about 0.4 to 0.8 moles, respectively.

[0135] The automotive or industrial gear oil of any one of the preceding sentences, wherein the sulfurized olefin is present at 0.1 to 8 wt.%.

[0136] The automotive or industrial gear oil of any one of the preceding sentences, wherein the sulfurized olefin is present at 0.2 to 6 wt.%.

[0137] The automotive or industrial gear oil of any one of the preceding sentences, wherein the sulfurized olefin is present at 0.5 to 5 wt.%.

[0138] The automotive or industrial gear oil of any one of the preceding sentences, wherein the sulfurized olefin provides 0.5 to 3 wt. % sulfur to the gear oil.

[0139] The automotive or industrial gear oil of any one of the preceding sentences, wherein the sulfurized olefin provides 0.75 to 2.75 wt. % sulfur to the gear oil.

[0140] The automotive or industrial gear oil of any one of the preceding sentences, wherein the sulfurized olefin provides 1 to 2.5 wt. % sulfur to the gear oil.

[0141] The automotive or industrial gear oil of any of the preceding sentences, further comprising 0.01 to 5.0 wt. % of an amine alkyl(thio)phosphate compound.

[0142] The automotive or industrial gear oil of any preceding sentence, further comprising 0.2 to 3 wt. % of an amine alkyl(thio)phosphate compound.

[0143] The automotive or industrial gear oil of any preceding sentence, further comprising 0.6 to 2 wt. % of an amine alkyl(thio)phosphate compound.

[0144] The automotive or industrial gear oil of any preceding sentence, further comprising 0.7 to 1.75 wt. % of an amine alkyl(thio)phosphate compound.

[0145] The automotive or industrial gear oil of any of the preceding sentences, further comprising 0.2 to 1.2 wt. % of an amine alkyl(thio)phosphate compound.

[0146] The automotive or industrial gear oil of any preceding sentence, further comprising 0.5 to 2.0 wt. % of an amine alkyl(thio)phosphate compound.

[0147] The automotive or industrial gear oil of any one of the preceding sentences, further comprising 0.55 to 1.4 wt. % of an amine alkyl(thio)phosphate compound.

[0148] The automotive or industrial gear oil of any one of the preceding sentences, further comprising 0.6 to 1.3 wt. % of an amine alkyl(thio)phosphate compound.

[0149] The automotive or industrial gear oil of any one of the preceding sentences, further comprising 0.7 to 1.2 wt. % of an amine alkyl(thio)phosphate compound.

[0150] The automotive or industrial gear oil of any preceding sentence, further comprising 1 to 2 wt. % of an amine alkyl(thio)phosphate compound.

[0151] The automotive or industrial gear oil of any preceding sentence, further comprising 1.5 to 2 wt. % of an amine alkyl(thio)phosphate compound.

[0152] The automotive or industrial gear oil of any preceding sentence, further comprising 1.2 to 1.8 wt. % of an amine alkyl(thio)phosphate compound.

[0153] The automotive or industrial gear oil of any preceding sentence, further comprising 1.8 to 2.2 wt. % of an amine alkyl(thio)phosphate compound.

[0154] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 200 to 3000 ppm.

[0155] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 400 to 2000 ppm.

[0156] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 300 to 2000 ppm.

[0157] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 600 to 1500 ppm.

[0158] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 700 to 1100 ppm.

[0159] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 900 to 1900 ppm.

[0160] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 1100 to 1800 ppm.

[0161] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 1200 to 1600 ppm.

[0162] The automotive or industrial gear oil of any of the preceding sentences, further comprising an amine alkyl(thio)phosphate compound suitable for providing phosphorus to the gear oil in an amount of 1500 to 2000 ppm.

[0163] The automotive or industrial gear oil of any one of the preceding sentences, wherein the amine alkyl(thio)phosphate comprises an amine phosphate.

[0164] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the amine phosphate comprises a substantially sulfur-free alkyl phosphate amine salt, wherein at least about 30 mole percent of the phosphorus atoms are in an alkyl pyrophosphate salt structure, and at least about 80 mole percent of the alkyl groups are secondary alkyl groups of from about 3 to about 12 carbon atoms.

[0165] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the amine phosphate comprises a substantially sulfur-free alkyl phosphate amine salt, wherein at least about 30 mole percent of the phosphorus atoms are in an alkyl pyrophosphate salt structure, and wherein at least about 25 mole percent of the alkyl groups in such sulfur-free alkyl phosphates can be primary alkyl groups of from about 3 to about 12 carbon atoms.

[0166] The automotive or industrial gear oil of any one of the preceding sentences, wherein the amine comprises 2-ethylhexylamine.

[0167] The automotive or industrial gear oil of any of the preceding sentences, wherein the amine alkyl(thio)phosphate comprises an amine alkyl thiophosphate.

[0168] The automotive or industrial gear oil of any one of the preceding sentences, wherein the alkylthiophosphate of the amine alkylthiophosphate comprises a dialkyldithiophosphate.

[0169] Amines are C8-C 20 10. The automotive or industrial gear oil of any one of the preceding sentences, comprising an alkylamine.

[0170] The metal alkylthiophosphate is represented by the formula: [ka] In the formula, R 25 and R 26 are independently hydrogen, hydrocarbyl groups, or mixtures thereof, provided that R 25 and R 26 The automotive or industrial gear oil of any one of the preceding sentences, wherein at least one of the groups is a hydrocarbyl group.

[0171] Metal alkylthiophosphates are R 25 and R 26 are independently hydrogen, alkyl or cycloalkyl groups, or mixtures thereof, provided that R 25 and R 26 wherein at least one of is an alkyl or cycloalkyl group having 1 to 30 carbon atoms.

[0172] Metal alkylthiophosphates are R 25 and R 26are independently hydrogen, alkyl or cycloalkyl groups, or mixtures thereof, provided that R 25 and R 26 and n is an alkyl or cycloalkyl group having from 2 to 20 carbon atoms.

[0173] Metal alkylthiophosphates are R 25 and R 26 are independently hydrogen, alkyl or cycloalkyl groups, or mixtures thereof, provided that R 25 and R 26 wherein at least one of is an alkyl or cycloalkyl group having 2 to 15 carbon atoms.

[0174] Metal alkylthiophosphates are R 25 and R 26 are independently hydrogen, alkyl or cycloalkyl groups, or mixtures thereof, provided that R 25 and R 26 wherein at least one of is a secondary alkyl group having 2 to 8 carbon atoms.

[0175] Metal alkylthiophosphates are R 25 and R 26 are independently hydrogen, alkyl or cycloalkyl groups, or mixtures thereof, provided that R 25 and R 26 wherein at least one of is a secondary alkyl group having 3 to 6 carbon atoms.

[0176] The automotive or industrial gear oil of any one of the preceding sentences, wherein the metal alkylthiophosphate comprises a zinc dialkyldithiophosphate.

[0177] 10. The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate comprises, consists essentially of, or consists of a secondary zinc dialkyldithiophosphate.

[0178] The automotive or industrial gear oil of any one of the preceding sentences, wherein the alkyl of the zinc dialkyldithiophosphate contains 3 to 6 carbon atoms.

[0179] The automotive or industrial gear oil of any one of the preceding sentences, wherein the alkyl of the zinc dialkyldithiophosphate contains 3 carbon atoms.

[0180] The automotive or industrial gear oil of any one of the preceding sentences, wherein the alkyl of the zinc dialkyldithiophosphate contains 6 carbon atoms.

[0181] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate provides 0.02 to 0.2 wt. % zinc to the automotive or industrial gear oil.

[0182] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate provides 0.02 to 0.095 wt. % zinc to the automotive or industrial gear oil.

[0183] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate provides 0.025 to 0.085 wt. % zinc to the automotive or industrial gear oil.

[0184] 10. The automotive or industrial gear oil of any preceding claim, wherein the zinc dialkyldithiophosphate provides 0.03 to 0.075 wt. % zinc to the automotive or industrial gear oil.

[0185] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate is present at 0.15 to 0.8 wt. %.

[0186] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate is present at 0.2 to 0.75 wt.%.

[0187] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate is present in an amount of from 0.25 to 0.70.

[0188] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate provides 0.025 to 0.19 wt. % zinc to the automotive or industrial gear oil.

[0189] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate provides 0.03 to 0.18 wt. % zinc to the automotive or industrial gear oil.

[0190] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate is present at 0.2 to 2 wt. %.

[0191] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate is present at 0.25 to 1.9 wt. %.

[0192] The automotive or industrial gear oil of any one of the preceding sentences, wherein the zinc dialkyldithiophosphate is present at 0.3 to 1.8 wt.%.

[0193] The automotive or industrial gear oil of any one of the preceding sentences, further comprising 2,5-dimercapto-1,3,4-thiadiazole.

[0194] The automotive or industrial gear oil of any one of the preceding sentences, wherein the lubricant contains a total sulfur level of about 0.75 to about 5 wt. %.

[0195] The automotive or industrial gear oil of any one of the preceding sentences, wherein the lubricant contains a total phosphorus level of about 0.01 to about 0.5 wt.%.

[0196] 10. A method for minimizing power losses in a driveline power transmission device, comprising providing to the driveline power transmission device an automotive or industrial gear oil according to any one of the preceding sentences and operating the driveline power transmission device.

[0197] The method of any one of the preceding sentences, wherein the driveline power transmission includes an axle.

[0198] The method of any one of the preceding sentences, wherein the driveline power transmission includes a bearing.

[0199] The method of any one of the preceding sentences, wherein the driveline power transmission includes gears.

[0200] A method for minimizing the operating temperature of gears, comprising lubricating the gears with an automotive or industrial gear oil as claimed in any one of the preceding sentences directed to the automotive or industrial gear oil; and operating the gears.

[0201] A method for improving the operating efficiency of gears, comprising lubricating the gears with an automotive or industrial gear oil as claimed in any one of the preceding sentences directed to the automotive or industrial gear oil, and operating the gears.

[0202] While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the scope of the subject invention. In this regard, the scope of the present invention is intended to be limited only by the claims that follow. The present invention provides, for example, the following items. (Item 1) 1. An automotive or industrial gear oil, comprising: a. Oil of lubricating viscosity; b.Formula R 1 -S x -R 2 (In the formula, R 1 and R 2 and 0.01 to 10 weight percent of a sulfurized olefin comprising a mixture of sulfurized olefins of formula (I), (II), (III), (IV), (IV), (IV), (V), (VI), (VII ... c. 0.1 to 2 weight percent of a metal alkylthiophosphate. (Item 2) 2. The automotive or industrial gear oil according to item 1, further comprising 0.01 to 5.0 wt. % of an amine alkyl(thio)phosphate compound. (Item 3) 3. The automotive or industrial gear oil of claim 2, wherein the amine alkyl(thio)phosphate comprises an amine phosphate. (Item 4) 3. The automotive or industrial gear oil of item 2, wherein the amine phosphate comprises a substantially sulfur-free alkyl phosphate amine salt, at least about 30 mole percent of the phosphorus atoms are in an alkyl pyrophosphate salt structure, and at least about 80 mole percent of the alkyl groups are secondary alkyl groups of from about 3 to about 12 carbon atoms. (Item 5) 3. The automotive or industrial gear oil of claim 2, wherein the amine phosphate comprises a substantially sulfur-free alkyl phosphate amine salt, wherein at least about 30 mole percent of the phosphorus atoms are in an alkyl pyrophosphate salt structure, and wherein at least about 25 mole percent of the alkyl groups in such sulfur-free alkyl phosphates can be primary alkyl groups of from about 3 to about 12 carbon atoms. (Item 6) 6. The automotive or industrial gear oil according to any one of items 2 to 5, wherein the amine comprises 2-ethylhexylamine. (Item 7) 8. The automotive or industrial gear oil of any one of the preceding items, wherein the amine phosphate is present at 0.5 to 2.0 weight percent. (Item 8) 3. The automotive or industrial gear oil of claim 2, wherein the amine alkyl(thio)phosphate comprises an amine alkylthiophosphate. (Item 9) 9. The automotive or industrial gear oil according to claim 8, wherein the alkylthiophosphate of the amine alkylthiophosphate comprises a dialkyldithiophosphate. (Item 10) The amine is C 8 ~C 20 10. The automotive or industrial gear oil according to item 8 or 9, comprising an alkylamine of the formula: (Item 11) 11. The automotive or industrial gear oil of any one of items 8 to 10, wherein the amine alkylthiophosphate is present at 0.5 to 2.0 weight percent. (Item 12) 8. The automotive or industrial gear oil of any one of the preceding items, wherein the metal alkylthiophosphate comprises a zinc dialkyldithiophosphate. (Item 13) 13. The automotive or industrial gear oil of item 12, wherein the zinc dialkyldithiophosphate comprises, consists essentially of, or consists of a secondary zinc dialkyldithiophosphate. (Item 14) 14. The automotive or industrial gear oil according to item 13, wherein the alkyl of the zinc dialkyldithiophosphate contains 3 to 6 carbon atoms. (Item 15) 14. The automotive or industrial gear oil according to item 13, wherein the alkyl of the zinc dialkyldithiophosphate contains 3 carbon atoms. (Item 16) 14. The automotive or industrial gear oil according to item 13, wherein the alkyl of the zinc dialkyldithiophosphate contains 6 carbon atoms. (Item 17) 14. The automotive or industrial gear oil according to item 12 or 13, wherein the zinc dialkyldithiophosphate provides 0.02 to 0.2 wt. % zinc to the automotive or industrial gear oil. (Item 18) 8. The automotive or industrial gear oil of any one of the preceding items, further comprising 2,5-dimercapto-1,3,4-thiadiazole. (Item 19) 8. The automotive or industrial gear oil of any one of the preceding items, wherein the lubricant contains a total sulfur level of about 0.75 to about 5 wt. %. (Item 20) 8. The automotive or industrial gear oil of any one of the preceding items, wherein the lubricant contains a total phosphorus level of about 0.01 to about 0.5 wt. %. (Item 21) 10. A method of minimizing power losses in a driveline transmission device, comprising providing to the driveline transmission device an automotive or industrial gear oil according to any one of the preceding items and operating the driveline transmission device. (Item 22) 22. The method of claim 21, wherein the driveline power transmission includes an axle. (Item 23) 22. The method of claim 21, wherein the driveline power transmission includes a bearing. (Item 24) 22. The method of claim 21, wherein the driveline transmission includes gears. (Item 25) 19. A method of minimizing the operating temperature of gears, comprising lubricating the gears with the automotive or industrial gear oil according to any one of items 1 to 18, and operating the gears. (Item 26) 19. A method for improving the operating efficiency of gears, comprising lubricating the gears with the automotive or industrial gear oil according to any one of items 1 to 18, and operating the gears.

Claims

1. 1. An automotive or industrial gear oil, comprising: a. an oil of lubricating viscosity; b. 2 to 5 weight percent sulfurized isobutylene, wherein the sulfurized isobutylene has a sulfur content of about 10 to about 50 weight percent; c. 0.25 to 2 wt. % of a metal alkylthiophosphate, wherein the metal comprises zinc; d. 0.5 to 5 wt. % of an amine alkyl (thio)phosphate compound; Including, An automotive or industrial gear oil wherein the amount of sulfurized isobutylene present is suitable to provide said automotive or industrial gear oil with sulfur in an amount of 0.5 to 3 weight percent sulfur.

2. 10. The automotive or industrial gear oil of claim 1, wherein the amine alkyl(thio)phosphate comprises an amine phosphate.

3. 10. The automotive or industrial gear oil of claim 1, wherein the amine phosphate comprises a substantially sulfur-free alkyl phosphate amine salt, at least about 30 mole percent of the phosphorus atoms are in an alkyl pyrophosphate salt structure, and at least about 80 mole percent of the alkyl groups are secondary alkyl groups of from about 3 to about 12 carbon atoms.

4. 10. The automotive or industrial gear oil of claim 1, wherein the amine phosphate comprises a substantially sulfur-free alkyl phosphate amine salt, wherein at least about 30 mole percent of the phosphorus atoms are in an alkyl pyrophosphate salt structure, and wherein at least about 25 mole percent of the alkyl groups in such sulfur-free alkyl phosphates can be primary alkyl groups of from about 3 to about 12 carbon atoms.

5. 5. The automotive or industrial gear oil of any one of claims 1 to 4, wherein the amine comprises 2-ethylhexylamine.

6. 6. The automotive or industrial gear oil of any one of claims 1 to 5, wherein the amine phosphate is present at 0.5 to 2.0 weight percent.

7. 10. The automotive or industrial gear oil of claim 1, wherein the amine alkyl(thio)phosphate comprises an amine alkylthiophosphate.

8. 8. The automotive or industrial gear oil of claim 7, wherein the alkylthiophosphate of the amine alkylthiophosphate comprises a dialkyldithiophosphate.

9. The amine is C ８ ~C ２０ 9. The automotive or industrial gear oil of claim 7 or 8, comprising an alkyl amine of the formula:

10. 10. The automotive or industrial gear oil of any one of claims 7 to 9, wherein the amine alkylthiophosphate is present at 0.5 to 2.0 weight percent.

11. 11. The automotive or industrial gear oil of any one of claims 1 to 10, wherein the metal alkylthiophosphate comprises a zinc dialkyldithiophosphate.

12. 12. The automotive or industrial gear oil of claim 11, wherein the zinc dialkyldithiophosphate comprises, consists essentially of, or consists of a secondary zinc dialkyldithiophosphate.

13. 13. The automotive or industrial gear oil of claim 12, wherein the alkyl of the zinc dialkyldithiophosphate contains 3 to 6 carbon atoms.

14. 13. The automotive or industrial gear oil of claim 12, wherein the alkyl of the zinc dialkyldithiophosphate contains 3 carbon atoms.

15. 13. The automotive or industrial gear oil of claim 12, wherein the alkyl of the zinc dialkyldithiophosphate contains 6 carbon atoms.

16. 13. The automotive or industrial gear oil of claim 11 or 12, wherein the zinc dialkyldithiophosphate provides 0.02 to 0.2 wt. % zinc to the automotive or industrial gear oil.

17. 17. The automotive or industrial gear oil of any one of claims 1 to 16, further comprising 2,5-dimercapto-1,3,4-thiadiazole.

18. 18. The automotive or industrial gear oil of any one of claims 1 to 17, wherein the lubricant contains a total sulfur level of from about 0.75 to about 5 wt. %.

19. 19. The automotive or industrial gear oil of any one of claims 1 to 18, wherein the lubricant contains a total phosphorus level of about 0.01 to about 0.5 wt. %.

20. 10. The automotive or industrial gear oil of claim 1, wherein the automotive or industrial gear oil contains 2.3 to 5 weight percent sulfurized isobutylene.

21. 21. A method of minimizing power losses in a driveline power transmission device, comprising providing to the driveline power transmission device an automotive or industrial gear oil according to any one of claims 1 to 20, and operating the driveline power transmission device.

22. 22. The method of claim 21, wherein the driveline transmission includes an axle.

23. The method of claim 21 , wherein the driveline transmission includes a bearing.

24. The method of claim 21 , wherein the driveline transmission includes a gear.

25. 21. A method of minimizing the operating temperature of gears, comprising lubricating said gears with the automotive or industrial gear oil of any one of claims 1 to 20, and operating said gears.

26. 21. A method of improving the operating efficiency of gears, comprising lubricating said gears with the automotive or industrial gear oil of any one of claims 1 to 20, and operating said gears.

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