Provided is a low sulfated ash engine oil lubricant composition containing organic friction modifiers with improved fuel economy and corrosion resistance. The lubricant composition includes one or more metal free corrosion inhibitors having an organic acid group and/or one or more organo metallic naphthalene molecules having a ASTM D2896 total base number less than 3 mg KOH/g. The resulting lubricant composition improves ASTM D6557 corrosion protection for low sulfated ash engine oils containing organic friction modifiers, while maintaining exceptional fuel economy performance.

A lubricating oil composition is described. The composition includes a base oil, a first succinimide dispersant composition comprising a reaction product of a hydrocarbyl succinimide and an aromatic glycidyl ether having a structure:

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wherein R.sub.1 is an aryl or alkaryl group having 4 to 20 carbon atoms, and R.sub.2 and R.sub.3 are independently a hydrogen atom, an alkyl group, or an aryl group; and a second succinimide dispersant.

The invention provides a lubricating oil composition comprising: a base oil; and coated particles made of nanoparticles and phosphonic acid coating at least a portion of the surface of the nanoparticles.

A method of reducing low-speed pre-ignition (LSPI) in a direct-injected spark-ignited internal combustion engine comprising lubricating the crankcase of the engine with a composition comprising a combination of a molybdenum-containing additive and a boron-containing additive. Preferably, the composition comprises a calcium detergent providing a calcium content of at least 0.08 wt. %, based on the weight of the lubricating oil composition.

The engine lubricating system can become contaminated with carbon deposits and sludge. Sludge is where the combustion by-products that have entered the oil base saturate this oil base, thus forming a thick carbon rich substance. Sludge is not wanted within the engine. Sludge and or carbon deposits in the motor oil cause problems. Such carbon deposits form in the motor oil from heat, pressure, and namely combustion gases that have leaked pasted the piston rings. Turpentine and terpenes, hereafter referred to as “terpenes”, have shown that these chemicals can breakdown carbon which has been deposited within the engine's oil base.

Disclosed is a method for reducing corrosion in a hybrid engine. The method includes the steps of lubricating a hybrid engine with a lubricating oil composition having a major amount of an oil of lubricating viscosity; a minor amount of a salicylate detergent derived from an isomerized normal alpha olefin; and a minor amount of a dispersant.

A lubricating oil composition for a transmission, the composition including: (A) a lubricant base oil comprising a mineral base oil and/or a synthetic base oil; and (B) a poly(meth)acrylate having a weight average molecular weight of no more than 25,000, wherein the composition has a kinematic viscosity at 100° C. of 2.5 to 4.9 mm.sup.2/s.

Provided is a mineral base oil satisfying the following requirements (I) to (III): Requirement (I): a kinematic viscosity at 100° C. is 2 mm.sup.2/s or more and less than 7 mm.sup.2/s; Requirement (II): a viscosity index is 100 or more; and Requirement (III): a temperature gradient Δ|η*| of complex viscosity between two temperature points −10° C. and −25° C. is 60 Pa.Math.s/° C. or less as measured with a rotary rheometer under conditions at an angular velocity of 6.3 rad/s and a strain amount of 0.1 to 100%. The foregoing mineral base oil can become a lubricating oil composition having desirable low-temperature viscosity characteristics, including low-temperature fuel consumption and low-temperature engine start-up performance, and also having excellent high-temperature piston detergency.

A transmission fluid composition contains a major amount of a lubricating oil basestock, and a minor amount of an additive package comprising: (i) a mixture comprising two or more phosphites and/or phosphates; (ii) one or more thioester compounds; (iii) one or more zinc dihydrocarbyl dithiophosphate compounds; and (iv) one or more oil-soluble or dispersible molybdenum-containing compounds. Such a transmission fluid may be used for controlling and/or reducing wear, e.g., in a manual transmission.

A refrigeration cycle apparatus including a refrigeration circuit, the refrigeration circuit including a compressor, an outdoor heat exchanger, an indoor heat exchanger, and an expansion valve, wherein a refrigerant is sealed within the refrigeration circuit, the refrigerant contains trifluoroiodomethane, the compressor is filled with a refrigerator oil, and the refrigerator oil contains at least one of a first compound represented by the following chemical formula 1 and a second compound represented by the following chemical formula 2:

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