A premium synthetic lubricating oil base stock having a high VI and low pourpoint is made by hydroisomerizing a Fischer-Tropschsynthesized waxy, paraffinic feed wax and then dewaxing the hydroisomerate toform a 650-750 °F+ dewaxate. The waxy feed has an initialboiling point in the range of about 650-750 °F, from which itcontinuously boils up to at least 1050 °F and has a T90-T10 temperaturedifference of at least 350 °F. The feed is preferably hydroisomerizedwithout any pretreatment, other than optional fractionation. The650-750 °F+ dewaxate is fractionated into two or more base stocks ofdifferent viscosity.
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