Abstract: Novel compositions, useful as additives for normally liquid fuels to impart dispersancy, anti-icing and rust inhibiting properties thereto, comprise salts of amines prepared by the Mannich reaction between a hydroxy-substituted aromatic compound, usually an alkylphenol in which the alkyl group contains at least about six carbon atoms; formaldehyde or a reversible polymer thereof; and a hydroxyalkyl-substituted amine such as diethanolamine. The acid portion of the salt is preferably derived from a carboxylic acid containing about 14-24 carbon atoms especially an aliphatic radical-substituted succinic acid or an acidic ester thereof. Epoxide adducts of such salts are useful for the same purposes.