Engine oil having dispersant and aldehyde/epoxide for improved seal performance, sludge and deposit performance

摘要

Disclosed is a lubricating composition having a major amount of an oil of lubrication viscosity and a minor amount of (A) a nitrogen containing dispersant with a total base number of from 20 to 160 on an oil-free basis wherein the improvement comprises adding to said dispersant; the dispersant comprising a Mannich reaction product and/or a reaction product of a hydrocarbyl-substituted succinic acylating agent with ammonia or an amine; (B) a sludge preventing/seal protecting additive of at least one aldehyde or epoxide or mixtures thereof.