Molecular distillation of methyl alkyl siloxanes of the formula ##STR1## wherein R.sub.1 and R.sub.2 are alkyl groups of 4-20 carbon atoms and m and p are integers to produce a distillate having a molecular weight fraction wherein the sum of m and p is about 4, produces an improved lubricant for the video disc, a lubricant that is stable to long term storage and to wide variations in temperature and relative humidity.