An improved hydrotreating catalyst and process for making a base oil product wherein the catalyst comprises a base extrudate that includes a high nanopore volume amorphous silica alumina (ASA) and an alumina. The catalyst and process generally involve the use of a high nanopore volume ASA/alumina based catalyst to produce hydrotreated dewaxed base oil products by contacting the catalyst with a hydrocarbon feedstock. The catalyst base extrudate advantageously comprises an amorphous silica alumina having a pore volume in the 11-20 nm pore diameter range of 0.2 to 0.9 cc/g and an alumina having, a pore volume in the 11-20 nm pore diameter range of 0.01 to 1.0 cc/g, with the base extrudate formed from the amorphous silica alumina and the alumina having a total pore volume in the 2-50 nm pore diameter range of 0.12 to 1.80 cc/g. The catalyst further comprises at least one modifier element from Groups 6 to 10 and Group 14 of the Periodic Table. The catalyst and process provide improved aromatics saturation.