| abstract |
A fully formulated crankcase lubricating oil composition containing between about 0.1 and 10 wt. % of a tetrapolymer of 4-vinylpyridine (4-VP), a first alkyl methacrylate of the formula: <IMAGE> a second alkyl methacrylate of the formula: <IMAGE> and a third alkyl methacrylate of the formula: <IMAGE> where R is alkyl of from 1 to 6 carbons, R1 is alkyl of from 10 to 15 carbons and R2 is alkyl of from 16 to 20 carbons, of a molecular weight between about 25,000 and 2,500,000 having a component ratio of 4-VP:C1 to C6 alkyl methacrylate:C10-C15 alkyl methacrylate:C16-C20 alkyl methacrylate of between about 2:10:78:10 and 10:30:30:30 and between about 0.1 and 5 wt. % of a calcium containing rust inhibitor, said composition having a sulfated metal ash content of between about 0.05 and 1 wt. %. |