A process for preparing a salt of a sulfurized alkyl-substituted hydroxyaromatic composition having a reduced content of unsulfurized alkyl-substituted hydroxyaromatic compound and its unsulfurized metal salt, the process comprising the steps of: (a) providing a neutral or overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition comprising (i) a salt of a sulfurized alkyl-substituted hydroxyaromatic compound; (ii) an unsulfurized alkyl-substituted hydroxyaromatic compound and (iii) an unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound; wherein the alkyl-substituted hydroxyaromatic compound is derived from alkylation of a hydroxyaromatic compound with one or more olefins comprising C 9 to C 18 oligomers of monomers selected from propylene, butylene or mixtures thereof; (b) protonating the unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound with an effective amount of an acidic compound capable of protonating the unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound, wherein the effective amount of the acidic compound is from 1 wt. % to 25 wt. %, based on the total amount of the neutral or overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition, wherein the acidic compound is selected from saturated carboxylic acids, unsaturated carboxylic acids, organic sulfonic acids, ammonium salts, and peroxides; and (c) removing the unsulfurized alkyl-substituted hydroxyaromatic compound and the protonated unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound from the composition, wherein the step of removing the unsulfurized alkyl-substituted hydroxyaromatic compound and the protonated unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound from the composition comprises distilling the unsulfurized alkyl-substituted hydroxyaromatic compound and the protonated unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound from the composition of step (b). (a) providing a neutral or overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition comprising (i) a salt of a sulfurized alkyl-substituted hydroxyaromatic compound; (ii) an unsulfurized alkyl-substituted hydroxyaromatic compound and (iii) an unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound; wherein the alkyl-substituted hydroxyaromatic compound is derived from alkylation of a hydroxyaromatic compound with one or more olefins comprising C 9 to C 18 oligomers of monomers selected from propylene, butylene or mixtures thereof; (b) protonating the unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound with an effective amount of an acidic compound capable of protonating the unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound, wherein the effective amount of the acidic compound is from 1 wt. % to 25 wt. %, based on the total amount of the neutral or overbased salt of a sulfurized alkyl-substituted hydroxyaromatic composition, wherein the acidic compound is selected from saturated carboxylic acids, unsaturated carboxylic acids, organic sulfonic acids, ammonium salts, and peroxides; and (c) removing the unsulfurized alkyl-substituted hydroxyaromatic compound and the protonated unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound from the composition, wherein the step of removing the unsulfurized alkyl-substituted hydroxyaromatic compound and the protonated unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound from the composition comprises distilling the unsulfurized alkyl-substituted hydroxyaromatic compound and the protonated unsulfurized metal salt of the alkyl-substituted hydroxyaromatic compound from the composition of step (b).