A urea grease of the invention is prepared by applying shear at a shear rate of 10.sup.2 s.sup.−1 or more to a mixture solution of an amine mixture containing an alicyclic monoamine and a chain aliphatic monoamine, and a diisocyanate compound to cause a reaction in the mixture, in which the urea grease has Peak High32-64s of 1.5 or less and Level High32-64s of 10 or less according to an FAG method.

The present disclosure provides for a lubricant formulation and a method of forming the lubricant formulation for use in an internal combustion engine. The lubricant formulation includes a base oil and an esterified oil-soluble polyalkylene glycol (E-OSP) of Formula (I): R.sup.1 [O(R.sup.2O).sub.n(R.sup.3O).sub.m(C═O)R.sup.4].sub.p wherein R.sup.1 is a linear alkyl having 1 to 18 carbon atoms, a branched alkyl having 4 to 18 carbon atoms or an aryl with 6 to 30 carbon atoms; R.sup.2O is an oxypropylene moiety derived from 1, 2-propylene oxide; R.sup.3O is an oxybutylene moiety derived from butylene oxide, wherein R.sup.2O and R.sup.3O are in a block or a random distribution; R.sup.4 is a linear alkyl with 1 to 18 carbon atoms, a branched alkyl with 4 to 18 carbon atoms or an aryl with 6 to 18 carbon atoms; n and m are each independently integers ranging from 0 to 20 wherein n+m is greater than 0, and p is an integer from 1 to 4.

Proposed is a mineral lubricating base oil having improved low-temperature performance, in which the lubricating base oil has kinematic viscosity of 9.0 cSt or less (at 40° C.), kinematic viscosity of 2.5 cSt or less (at 100° C.), and a pour point of −50° C. or less.

Proposed is a mineral lubricating base oil having improved low-temperature performance, in which the lubricating base oil has kinematic viscosity of 9.0 cSt or less (at 40° C.), kinematic viscosity of 2.5 cSt or less (at 100° C.), and a pour point of −50° C. or less.

Use of a guanidinium-based ionic liquid as detergent in a lubricant composition, notably for lubricating marine engines. A lubricant composition including a guanidinium-based ionic liquid.

Provided is a lubricating oil composition containing a base oil (A) and an amine-based antioxidant (B), wherein the component (B) contains a phenyl-naphthylamine (B1), an alkylphenyl-naphthylamine (B2) and a di(alkylphenyl)amine (B3), the content of the component (B1) is 2.0 to 10.0% by mass relative to 100% by mass of the total amount of the component (B), the content of the component (B2) is 40.0 to 90.0% by mass relative to 100% by mass of the total amount of the component (B), and the content of the component (B3) is 8.0 to 50.0% by mass relative to 100% by mass of the total amount of the component (B). The lubricating oil composition maintains excellent oxidation stability even in long-term use in high-temperature environments, and has an excellent lifetime and is excellent also in a sludge preventing effect.

A lubricating oil composition comprising at least 50 percent by mass, based on the mass of the composition of an oil of lubricating viscosity and 0.01 to 25 percent by mass, based on the mass of the composition of a polymer comprising units (a) and one or both units (b) and (c):
—N(COR.sup.1)(CH.sub.2).sub.x—  (a)
—NH(CH.sub.2).sub.y—  (b)
—N(CH.sub.2CH.sub.2-k(CH.sub.3).sub.kCOOR.sup.2)(CH.sub.2).sub.z   (c) where the total number (n) of units (a), (b) and (c) is an integer between 4 and 500; wherein x, y and z are independently 2 or 3; wherein k is zero or 1. The polymer shows good solubility in the lubricating oil and provides friction modification. A method of synthesising a polymer is also disclosed.

A lubricating oil composition for automotive transmissions is disclosed. It offers an automotive transmission (especially a fuel-saving type) which satisfies all requirements as regards the properties of resistance to churning, maintenance of the oil film and low-temperature viscosity. It comprises a GTL low viscosity base oil and a Group 1 high viscosity base oil.

A fluid includes a base stock and one or more additives. The base stock has a viscosity index of at least 80, and either a kinematic viscosity at 40° C. of at least 320 cSt or a kinematic viscosity at 100° C. of at least 14 cSt. The base stock includes greater than or equal to about 90 wt % saturates, less than or equal to about 10 wt % aromatics, and a sum of terminal/pendant propyl groups and terminal/pendant ethyl groups of at least 1.7 per 100 carbon atoms. The fluid has a thermal conductivity measured according to ASTM D7896 at 140° C. of 0.12 W/m.Math.K or greater.

A fluid includes a base stock and one or more additives. The base stock has a viscosity index of at least 80, and either a kinematic viscosity at 40° C. of at least 320 cSt or a kinematic viscosity at 100° C. of at least 14 cSt. The base stock includes greater than or equal to about 90 wt % saturates, less than or equal to about 10 wt % aromatics, and a sum of terminal/pendant propyl groups and terminal/pendant ethyl groups of at least 1.7 per 100 carbon atoms. The fluid has a thermal conductivity measured according to ASTM D7896 at 140° C. of 0.12 W/m.Math.K or greater.