| abstract |
The lubricating oil composition described is useful for the operation of internal combustion engines and has improved oxidation and wear characteristics. More particularly, the lubricating oil compositions of the invention comprise: (A) a main amount of oil having a lubricating viscosity; (B) at least about 1.0 by weight of at least one composition of a carboxylic derivative produced by reacting (B-1) at least one succinic acylating agent substituted with (B-2) at least one compound amine characterized by the presence in its structure of at least one HN group <in which the substituted succinic acylating agents consist of substitution groups and succinic groups, the substituent groups being derived from polyalkene, which are characterized by an Mn value from 1300 to approximately 5000 and an Mw / Mn value of 1.5 to approximately 4.5, these acylating agents being characterized by the presence in their structure of an average of at least 1.3 succinic groups for each weight equivalent of substituent groups; and (C) at least one manganese compound in an amount sufficient to constitute from 1 to about 500 ppm of manganese as a metal, provided that the manganese compound is not a neutral manganese dihydrocarbyl phosphorodithioate. The lubricating oil compositions can also contain other advantageous additives including (D) at least one metal phosphorodithioate dihydrocarbyl; (E) effective detergent amounts of at least one salt of a neutral or basic alkali metal of a sulfonic or carboxylic acid; and / or (F) at least one carboxylic ester derivative. In one embodiment, the lubricating oil compositions of the present invention contain the above-mentioned additives as well as other additives disclosed in the specification, in an amount sufficient to allow the oil to meet all of the requirements. APi service classification performance requirements |