A lubricating base stock useful for forming lubricants such as a multigrade automotive oils, automatic transmission oils, greases and the like is prepared by hydroisomerizing a waxy hydrocarbon feed fraction having an initial boiling point in the 650-750.degree. F. range and an end point of at least 1050.degree. F., synthesized by a slurry Fischer-Tropsch hydrocarbon synthesis process. The hydroisomerization forms a hydroisomerate containing the desired base stock which is recovered, without dewaxing the hydroisomerate. The hydroisomerization is conducted at conditions effective to convert at least 67 wt. % of the 650-750.degree. F.+ waxy feed hydrocarbons to lower boiling hydrocarbons. When combined with a standard lubricant additive package, these base stocks have been formed into multigrade automotive crankcase oils, transmission oils and hydraulic oils meeting the specifications for these oils.