Lubricants with enhanced low temperature properties

A vinylaromatic-maleic ester polymeric viscosity index improver in which the ester groups comprise at least a major molar proportion of primary alkyl groups falling in the range of C.sub.8 to C.sub.18 alkyl groups, about 50 to about 90 mol % of said primary alkyl groups being linear alkyl groups and the balance of said primary alkyl groups being branched chain alkyl groups, wherein at least 90 mol % of the ester groups are primary alkyl groups having 8, 10, 12, 14, 16 and 18 carbon atoms, wherein from 5 to 20 tool % of said primary alkyl groups are linear C.sub.8 alkyl groups, and wherein from 10 to 50 mol % of said primary alkyl groups are 2-ethylhexyl groups.