The present disclosure relates to methods of improving viscosity shear stability of a lubricating oil and lubricating oil composition comprising: a base oil of lubricating viscosity; an amount of one or more zinc dialkyl dithiophosphate compound(s);
wherein the lubricating oil composition has one or both of the following ratios: a) a ratio of KV40° C..sub.fresh to a weight % of zinc contributed by the one or more zinc dialkyl dithiophosphate compound(s) based on a total weight of the lubricating oil composition, of greater than 510, wherein KV40° C..sub.fresh is the kinematic viscosity of the fresh lubricating oil composition at 40° C.; and b) a ratio of KV40° C..sub.fresh to a weight % of phosphorus contributed by the one or more zinc dialkyl dithiophosphate compound(s) based on a total weight of the lubricating oil composition, of greater than 560, wherein KV40° C..sub.fresh is the kinematic viscosity of the fresh lubricating oil composition at 40° C.

The invention provides a grease composition for lubricating resins which contains a base oil, a diurea compound represented by formula (I) as a thickener: R.sup.1—NHCONH —R.sup.2—NHCONH—R.sup.3 (I) (wherein R.sup.2 represents a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R.sup.1 and R.sup.3 each independently represent a straight-chain or branched alkyl group having 8 to 22 carbon atoms), and a chained hydrocarbon polymer having a weight-average molecular weight of 20,000 to 300,000.

The invention provides a grease composition for lubricating resins which contains a base oil, a diurea compound represented by formula (I) as a thickener: R.sup.1—NHCONH —R.sup.2—NHCONH—R.sup.3 (I) (wherein R.sup.2 represents a bivalent aromatic hydrocarbon group having 6 to 15 carbon atoms, and R.sup.1 and R.sup.3 each independently represent a straight-chain or branched alkyl group having 8 to 22 carbon atoms), and a chained hydrocarbon polymer having a weight-average molecular weight of 20,000 to 300,000.

Embodiments of the present disclosure generally relate to diluent oils for viscosity modifiers and additive packages. Embodiments of the present disclosure also generally relate to lubricating oil compositions that include viscosity modifier concentrates and lubricating oil compositions that include additive package concentrates. Improved diluent oils capable of conveniently and cost effectively improving overall lubricant performance are provided.

Embodiments of the present disclosure generally relate to diluent oils for viscosity modifiers and additive packages. Embodiments of the present disclosure also generally relate to lubricating oil compositions that include viscosity modifier concentrates and lubricating oil compositions that include additive package concentrates. Improved diluent oils capable of conveniently and cost effectively improving overall lubricant performance are provided.

Provided is a lubricating oil composition that includes a major amount of a lubricant base oil and a minor amount of a viscosity index improver comprising a syndiotactic propylene-based ethylene-propylene copolymer comprising: a) 2 to 20% by weight of ethylene, b) 80 to 98% by weight of propylene; c) 50 to 99% of rr triads; and d) Mw (LS) of 10 to 250 kg/mol.

Provided is a lubricating oil composition that includes a major amount of a lubricant base oil and a minor amount of a viscosity index improver comprising a syndiotactic propylene-based ethylene-propylene copolymer comprising: a) 2 to 20% by weight of ethylene, b) 80 to 98% by weight of propylene; c) 50 to 99% of rr triads; and d) Mw (LS) of 10 to 250 kg/mol.

The invention provides a grease composition used for lubricating a mechanical part having a steel portion to be lubricated which performs a rolling motion and a rolling and sliding motion, containing a base oil, a thickener and an additive, wherein the additive includes at least one compound selected from the group consisting of polyethylene wax, oxidized polyethylene wax, polypropylene wax, montan wax and amide wax.

The invention provides a grease composition used for lubricating a mechanical part having a steel portion to be lubricated which performs a rolling motion and a rolling and sliding motion, containing a base oil, a thickener and an additive, wherein the additive includes at least one compound selected from the group consisting of polyethylene wax, oxidized polyethylene wax, polypropylene wax, montan wax and amide wax.

Provided herein are ethylene copolymers, methods for making such copolymers, and compositions made from such copolymers. The ethylene copolymers have 70 wt. % to 85 wt. % of units derived from ethylene and at least 12 wt. % of units derived from at least one α-olefin having 3 to 20 carbon atoms. The copolymers preferably further have a weight-average molecular weight (Mw) ranging from about 50,000 to about 200,000 g/mol, melting point of at least 100° C., ratio of Mw/Mn of about 1.5 to about 3.5, a content of group 4 metals of no more than 25 ppm, and a ratio of wt ppm Group 4 metals/wt ppm Group 5 metals of at least 3. Such copolymers may be particularly useful as viscosity modifiers for lubricating oil compositions.