A lubricating oil composition can include a major amount of an oil of lubricating viscosity and a minor amount of an alkaline earth metal phenol-based detergent. The lubricating oil composition can further have a BN of greater than 140 mg KOH/g, and further wherein the marine diesel cylinder lubricating oil composition is substantially free of unsulfurized tetrapropenyl phenol and its unsulfurized metal salt.

The invention is directed to a zinc-free lubricating composition for an internal combustion engine containing a phosphorus anti-wear agent, an ashless antioxidant, and an oxyalkylated phenol compound. The lubricating composition provides wear protection, deposit control, and improved acid control with reduced levels of metal-containing additives.

The disclosed technology provides a lubricating composition and a method of lubricating an internal combustion engine where the lubricating composition contains an oil of lubricating viscosity, one or more metal-containing, sulfur-free, alkyl-phenol based detergents, an alkaline earth metal sulfonate detergent, a polyisobutenyl succinimide dispersant, and a dispersant viscosity modifier having a number average molecular weight of at least 20,000. The lubricating composition of the present invention can be formulated to have lower HTHS viscosity, and reduced phosphorous content, while providing protection against adhesive wear.

A lubricating composition includes an oil of lubricating viscosity and an N-substituted hydroxyaromatic succinimide or a salt thereof.

A lubricating composition includes an oil of lubricating viscosity and a compound comprising a protected mercaptophenol. The protected mercaptophenol includes a mercapto group in which the hydrogen is substituted with a substituent of at least 5 carbons. The substituent is selected from hydroxy-substituted hydrocarbyl groups, poly(ether) groups, hydrocarbyl groups, and mixtures and salts thereof.

Provided herein are estolide compositions having high oxidative stability, said compositions comprising at least one compound of formula: ##STR00001##
in which n is an integer equal to or greater than 0; m is an integer equal to or greater than 1; R.sub.1, independently for each occurrence, is selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; R.sub.2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R.sub.3 and R.sub.4, independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched. Also provided herein are uses for the compositions and methods of preparing the same.

A lubricating composition includes at least one base oil, at least one borated dispersant, at least two antioxidants selected from amine antioxidants, phenolic antioxidants substituted with one or more linear or branched alkyl groups having from 1 to 30 carbon atoms, and mixtures thereof, and at least one phosphite polymer having the formula (I) wherein: each of the R.sup.1, R.sup.2, R.sup.3 and R.sup.4 can be independently selected from the C1-C20 alkyl, C3-C22 alkenyl, C6-C40 cycloalkyl, C7-C40 cycloalkenyl, C1-20 methoxy alkyl glycol ethers and YOH groups; Y is selected from C2-C40 alkylene, C2-C40 alkyl lactone, R.sup.7N(R.sup.8)R.sup.9 groups, in which R.sup.7, R.sup.8 and R.sup.9 are independently selected from hydrogen, C1-C20 alkyl, C3-C22 alkenyi, C6-C40 cycloalkyl, C7-C40 cycloalkenyl, C1-20 methoxy alkyl glycol ethers; m is an integer from 2 to 100; n is an integer from 1 to 1000.

Disclosed is a lubricating oil composition comprising an oil of lubricating viscosity and an oil soluble synergistic mixture of antioxidants, said mixture comprising: a) a hindered amine antioxidant according to formula (I) ##STR00001## wherein each R.sup.1 is independently selected from a substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; R.sup.2 is selected from the group consisting of a hydrogen atom or a, substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; each R.sup.3 is independently selected from the group consisting of a hydrogen atom or a, substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; each R.sup.4 is independently selected from the group consisting of a hydrogen atom or a, substituted or unsubstituted, branched or linear, C.sub.1-C.sub.20 hydrocarbyl group; n is an integer from 1 to 4; and m is an integer from 1 to 5; and b) a molybdenum succinimide complex.

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

The present invention provides a refrigerating machine oil comprising a base oil; a sulfide compound; and an orthophosphoric acid ester, wherein a content of the sulfide compound is 0.01 to 2.0% by mass and a content of the orthophosphoric acid ester is 0.1 to 5.0% by mass, based on a total amount of the refrigerating machine oil, and the refrigerating machine oil having a kinematic viscosity at 40? C. of 3 to 500 mm.sup.2/s.