Provided are a lubricating oil composition used in a diesel engine equipped with a forced-induction compressor, containing a base oil (A) containing a poly--olefin (A1), and a viscosity index improver (B) having an SSI (shear stability index) of 20 or less, having a distillation amount of a light fraction of 496 C. or less in a gas chromatography distillation test of less than 80% by volume, having a high retention of the effect of suppressing the formation of deposits that may occur inside the compressor, and being capable of retaining a high efficiency of the compressor for a long period of time, in the use thereof in a diesel engine equipped with a forced-induction compressor having an outlet temperature of the compressor becoming a high temperature reaching 190 C. or more, and a method for using the lubricating oil composition.

The invention provides a hydraulic fluid composition comprising a hydrocarbon component comprising more than 5 wt % of naphthenic oil and up to 95 wt % of renewable or recycled isoparaffinic oil, based on the total weight of the composition. The hydraulic fluid composition is useful as an arctic hydraulic fluid composition, shock absorber or automatic transmission fluid.

To provide a lubricating oil composition achieving both of high traction coefficient and excellent low temperature fluidity at a higher level and having a high flash point, which contains a naphthene-based synthetic oil (A) having a flash point of 140 C. or higher, a longifolene (B), and a predetermined monoester-based synthetic oil (C), a method for producing the lubricating oil composition, and a continuously variable transmission using the lubricating oil composition.

Provided are: a lubricant base oil capable of achieving both a high traction coefficient and an excellent low-temperature fluidity at a higher level and having a high flash point, which contains a ring-containing compound having at least (i) a crosslinked bicyclic ring where two rings are bonded while sharing 3 or more carbon atoms, and (ii) an acyloxy group or a hydrocarbyloxycarbonyl group each containing a branched hydrocarbon group with a main chain having 4 or more carbon atoms, a lubricating oil composition containing the lubricant base oil, and a continuously variable transmission using the lubricating oil composition.

Disclosed is a lubricating oil composition comprising: a major amount of an oil of lubricating viscosity, and an salicylate compound derived from isomerized normal alpha olefin (NAO) having from about 10 to about 40 carbon atoms, wherein the TBN of the salicylate compound is at least 600 mg KOH/g on an actives basis, and wherein the lubricating oil composition contains from about 0.12 to about 0.17 wt. % of calcium and is substantially free of magnesium. Also provided is a method of lubricating an engine with said lubricating oil composition.

The present invention provides a mineral base oil having a kinetic viscosity at 100 C. of 7 mm.sup.2/s or more and less than 10 mm.sup.2/s, a viscosity index of 100 or more, and a temperature gradient |*| complex viscosity between two temperature points of 5 C. and 15 C. of 240 mPa.Math.s/ C. or less as measured with a rotary rheometer at an angular velocity of 6.3 rad/s. The use of the mineral base oil enables easy preparation of a lubricating oil composition and a grease composition having excellent oxidation stability while ensuring the freedom of selection of additives.

In some embodiments, ethylene-propylene branched copolymers are synthesized with pyridyldiamido catalysts and a chain transfer agent, and their performance as viscosity modifiers in oil are detailed. In some embodiments, the present disclosure provides for ethylene-propylene branched copolymers having a shear thinning onset of less than about 0.01 rad/s and an HTHS value of less than about 3.3. In some embodiments, the ethylene-propylene branched copolymer is used as a viscosity modifier in a lubricating composition and a fuel composition.

A lubricating composition comprises a major amount of an oil of lubricating viscosity and 0.01 to 25 percent by mass, based on the mass of the composition of an oil-soluble copolymer. The copolymer comprises units (a) and units (b):
N(COR.sup.1)CH.sub.2CH.sub.2(a)
N(COR.sup.2)CH.sub.2CH.sub.2CH.sub.2(b)
wherein the polymer carries an inorganic or organic nucleophilic polymerisation terminating group (t), and an initiator group (i) connected to the N atom of a repeat unit (a) or (b), the initiator group (i) being effective to initiate the polymerisation of linear, branched or cyclic hydrocarbyl moieties. R.sup.1 and R.sup.2 are the same or different and comprise a single or a mixture of linear, branched or cyclic hydrocarbyl groups having 1-50 carbon atoms, some or all having 12-50 carbon atoms, or of at least one macro-monomeric hydrocarbyl group with more than 50 carbon atoms.

A comb copolymer A2 including at least two boronic ester functions, the copolymer including a main chain and side chains, and at least one portion of the side chains of the copolymer A2 made of oligomers. Also, a composition resulting from mixing at least one polydiol compound A1 and a copolymer A2. The compositions exhibit very varied rheological properties depending on the proportion of the compounds A1 and A2 used. Also, a lubricant composition including such a mixture and at least one lubricating oil. Also, use of this composition to lubricate a mechanical part.

Compositions include ether ester compounds derived from neo-acids, lubricating oil base stocks containing such ester compounds, and lubricating oil compositions containing such ester compounds. Methods can include making and formulating compositions containing ether ester compounds derived from neo-acids.