The present invention provides a hydraulic fluid comprising: (a) 40 to 2000 ppm by weight in terms of nitrogen content of a corrosion inhibiting agent which is one or more compounds of formula (I): ##STR00001## and/or tribologically acceptable salts thereof, wherein in formula (I): each R.sup.1 is independently a hydrocarbyl group comprising 1 to 10 carbon atoms, x is 0 to 4, each of R.sup.2 and R.sup.3 is independently hydrogen or a hydrocarbyl group comprising 1 to 20 carbon atoms, R.sup.4 is —NR.sup.5R.sup.6 or —OR.sup.7, each of R.sup.5 and R.sup.6 is independently an aryl group comprising 6 to 14 carbon atoms, optionally substituted with one or more hydrocarbyl groups comprising 1 to 20 carbon atoms, R.sup.7 is a hydrocarbyl group comprising 1 to 20 carbon atoms, and in each of said hydrocarbyl groups containing 2 or more carbon atoms, the carbon chain may, independently, optionally be interrupted by one or more ether groups; (b) 0.1 to 1% by weight of an ashless dispersant; and (c) a major amount of a base oil.

The present invention provides a hydraulic fluid comprising: (a) 40 to 2000 ppm by weight in terms of nitrogen content of a corrosion inhibiting agent which is one or more compounds of formula (I): ##STR00001## and/or tribologically acceptable salts thereof, wherein in formula (I): each R.sup.1 is independently a hydrocarbyl group comprising 1 to 10 carbon atoms, x is 0 to 4, each of R.sup.2 and R.sup.3 is independently hydrogen or a hydrocarbyl group comprising 1 to 20 carbon atoms, R.sup.4 is —NR.sup.5R.sup.6 or —OR.sup.7, each of R.sup.5 and R.sup.6 is independently an aryl group comprising 6 to 14 carbon atoms, optionally substituted with one or more hydrocarbyl groups comprising 1 to 20 carbon atoms, R.sup.7 is a hydrocarbyl group comprising 1 to 20 carbon atoms, and in each of said hydrocarbyl groups containing 2 or more carbon atoms, the carbon chain may, independently, optionally be interrupted by one or more ether groups; (b) 0.1 to 1% by weight of an ashless dispersant; and (c) a major amount of a base oil.

Compositions, including dispersants, derived from substituted succinic anhydrides and aromatic polyamines. Methods for making compositions, the methods including contacting a substituted succinic anhydride and an aromatic polyamine. Lubricants that include a composition derived from a substituted succinic anhydride and an aromatic polyamine. Methods for improving soot performance.

Compositions, including dispersants, derived from substituted succinic anhydrides and aromatic polyamines. Methods for making compositions, the methods including contacting a substituted succinic anhydride and an aromatic polyamine. Lubricants that include a composition derived from a substituted succinic anhydride and an aromatic polyamine. Methods for improving soot performance.

Compositions, including dispersants, derived from substituted succinic anhydrides and aromatic polyamines. Methods for making compositions, the methods including contacting a substituted succinic anhydride and an aromatic polyamine. Lubricants that include a composition derived from a substituted succinic anhydride and an aromatic polyamine. Methods for improving soot performance.

Compositions, including dispersants, derived from substituted succinic anhydrides and aromatic polyamines. Methods for making compositions, the methods including contacting a substituted succinic anhydride and an aromatic polyamine. Lubricants that include a composition derived from a substituted succinic anhydride and an aromatic polyamine. Methods for improving soot performance.

The instant disclosure generally relates to lubricating compositions having an oil of lubricating viscosity and a mixed dispersant additive package. The mixed dispersant additive package can include an acylated poly(1-olefin)-based dispersant and a poly-isobutylene succinimide dispersant where the ratio of the acylated poly(1-olefin)-based dispersant to the polyisobutylene succinimide dispersant in the lubricating composition is from 3:1 to 1:3.

The instant disclosure generally relates to lubricating compositions having an oil of lubricating viscosity and a mixed dispersant additive package. The mixed dispersant additive package can include an acylated poly(1-olefin)-based dispersant and a poly-isobutylene succinimide dispersant where the ratio of the acylated poly(1-olefin)-based dispersant to the polyisobutylene succinimide dispersant in the lubricating composition is from 3:1 to 1:3.

Use of a liquid fuel composition in an internal combustion engine, the internal combustion engine containing a lubricating composition for lubricating said internal combustion engine, wherein the liquid fuel composition comprises at least one nitrogen-containing detergent additive, for the purpose of reducing engine wear caused by the presence of soot in the lubricating composition.

Use of a liquid fuel composition in an internal combustion engine, the internal combustion engine containing a lubricating composition for lubricating said internal combustion engine, wherein the liquid fuel composition comprises at least one nitrogen-containing detergent additive, for the purpose of reducing engine wear caused by the presence of soot in the lubricating composition.