The invention relates to a gear pump for oil for an internal-combustion engine, in particular for motor vehicles, comprising a pump housing mounted on the motor and an outer rotor which is arranged in the pump housing, an inner rotor additionally being arranged within the outer rotor or within the pump housing and at least one suction and/or at least one pressure passage being provided in the pump housing, a drive further being present; the pump according to the invention is integrated in a drive wheel or guide pulley of the internal-combustion engine and the outer rotor or the outer rotors are driven by the drive wheel or the guide pulley.