abstract |
The invention relates to a lubricating composition comprising: (a) at least one sulfur-free hydrocarbyl phosphoric acid ester or salt, (b) at least one sulfur-containing hydrocarbyl phosphoric acid or salt, (c) an organic polysulfide, (d) at least one dispersant, and (e) at least one triazole metal deactivator. The composition may also include a thiadiazole derivative. This additive combination provides good antiwear and thermal stability properties, even under severe thermal conditions. These compositions also have good demulsibility properties. The above combination of additives provides the antiwear and extreme-pressure protection necessary for automotive and industrial gear applications. These additives additionally provide this protection without adversely effecting demulsibility properties of the lubricant. |