Lubricating Composition and Method of Lubricating Driveline Device

Abstract

The present invention relates to a lubricating composition containing: an oil of lubricating viscosity, a non-borated dispersant, a detergent, and an antiwear package comprising (a) a derivative of a hydroxycarboxylic acid, (b) an amine salt of a phosphoric acid ester, and (c) a phosphite having at least one hydrocarbyl group with 4 or more carbon atoms. The invention further provides for a method of lubricating a driveline device application by employing a lubricating composition containing the antiwear package.

Description

FIELD OF INVENTION[0001]The present invention relates to a lubricating composition containing: an oil of lubricating viscosity, a non-borated dispersant, a detergent, and an antiwear package comprising (a) a derivative of a hydroxycarboxylic acid, (b) an amine salt of a phosphoric acid ester, and (c) a phosphite having at least one hydrocarbyl group with 4 or more carbon atoms. The invention further provides for a method of lubricating a driveline device application by employing a lubricating composition containing the antiwear package.BACKGROUND OF THE INVENTION[0002]Oxidation of an oil of lubricating viscosity, especially an organic petroleum fluid, occurs in the presence of oxygen which leads to increased viscosity and sludge and / or deposit formation. Sludge and / or deposit formation is produced by a number of different mechanisms such as degradation of oil and decomposition products of lubricant additives. Using known lubricant additives containing an amine salt of a phosphorus c...

AI Technical Summary

Benefits of technology

This invention relates to a lubricating composition and method that can improve the performance of an automotive transmission or differential gears by reducing wear, scuffing, fatigue, ridging, extreme pressure, fuel economy / efficiency, oxidation control, friction performance, and deposit control. The technical effects of this invention are improved wear or fatigue performance in a driveline device, resulting in improved overall performance of the vehicle.

Problems solved by technology

The presence of sludge and other deposits interferes with seal performance leading to leakage and ultimately equipment failure for gears or bearings.

However, many of the phosphorus antiwear or extreme pressure additives contain sulphur.

Due to increasing environmental concerns, the presence of sulphur in antiwear or extreme pressure additives is becoming less desirable.

In addition, many of the sulphur-containing antiwear or extreme pressure additives evolve volatile sulphur species, resulting in lubricating compositions containing antiwear or extreme pressure additives having an odour, which may also be detrimental to the environment or evolve emissions that may be higher than increasingly tighter health and safety legislation specifies.

However, many of the antiwear or extreme pressure additives employed have at least one of (i) limited extreme pressure and antiwear performance over a wide range of operating conditions, (ii) limited oxidative stability, (iii) tendency to form deposits, or (iv) tendency to cause corrosion (for example copper corrosion).

In addition, many phosphorus antiwear or extreme pressure additives typically contain sulphur, which results in an odorous lubricating composition containing the phosphorus antiwear or extreme pressure additives.

Images