The present invention relates to formulated lubricant oils derived from a highly paraffinic basestock. The formulated lubricant oils of the present invention comprise a wax isomerate paraffinic hydrocarbon basestock component in which the extent of branching, as measured by the percentage of methyl hydrogens (BI), and the proximity of branching, as measured by the percentage of recurring methylene carbons which are four or more carbons removed from an end group or branch (CH2 > 4), are such that: (a) BI - 0.5(CH2 > 4)>15; and (b) BI + 0.85(CH2 >4)<45; as measured over the hydrocarbon basestock as a whole. Preferably, the wax isomerate basestocks to be used in the lubricating oils of the present invention have a biodegradability value of at least 50 % under OECD 301 B test. In addition, these basestock components have pour points of about -25 DEG C. or lower. They are also characterized by unexpectedly good low-temperature and high-temperature viscosities, with CCS viscosity at -15 DEG C. of not more than about 3500 cP, and with a kinematic viscosity at 100 DEG C. of about 5 cSt or greater. Desirable multigraded oils obtained using these basestocks may include 0W-, 5W-, 10W-, and 15W-XX grades (XX=20-60). |