Treatment of aluminiferous metal surfaces with an aqueous liquid composition which has a pH value in the range from 1.8 to 4.0 and comprises (A) from 0.01 to 1.0 g/L of phosphate ions, (B) from 0.01 to 0.5 g/L, measured as its total stoichiometric equivalent as metal, of water-soluble zirconium and titanium compounds, (C) from 0.01 to 2-0 g/L, measured as fluorine, of simple and/or complex fluoride anions; and (D) from 0.01 to 2.0 g/L of water-soluble polyamides that contain at least one tertiary amino or polyoxyalkylene moiety forms a highly corrosion-resistant, strongly paint-adherent, and low friction conversion coating on the metal surface.