A novel additive comprising a highly grafted, multi-functional olefin copolymer comprising a graft and amine-derivatized copolymer prepared from ethylene and at least one C.sub.3 to C.sub.23 alpha-monoolefin and, optionally, a polyene, wherein the copolymer of ethylene and at least one C.sub.3 to C.sub.23 alpha-monoolefin has grafted thereon from 0.3 to 0.75 carboxylic groups per 1000 number average molecular weight units of olefin copolymer and wherein the olefin copolymer has a number average molecular weight of between 20,000 and 150,000, and lubricating oil concentrates and compositions containing the same are provided.