A method of making a hindered phenolic antioxidant is disclosed wherein the method comprises: reacting an ester of the formula: ##STR00001## wherein R.sup.1, R.sup.2, and R.sup.3 are independently selected alkyl groups and n is 0, 1, or 2, with an aliphatic polyhydroxyl alcohol of the general formula R(OH).sub.n wherein R is an aliphatic group of from 2 to about 12 carbon atoms and n is an integer of from 2 to 7, provided that one hydroxyl is primary and the others are secondary or tertiary, in the presence of a strong acid catalyst; then, neutralizing the strong acid catalyst with an overbased detergent; and isolating the hindered phenolic antioxidant after the neutralization step.