Binary systems Pd-X (X = Fe and Cu) have order-disorder transformations in solid-solution ranges. A sensitive parameter to atomic arrangement for a solution is the excess volume, which in itself is interesting from a thermodynamic perspective. In this study, using a combination of electromagnetic levitation and a static magnetic field, accurate measurements were taken of the density of liquid Pd-X alloys from which excess volumes were evaluated. The excess volumes of these binary systems were positive over the entire composition range. Hence, these order-disorder transformation systems have positive excess volumes in their liquid states. The results are analyzed using thermodynamic functions such as the excess Gibbs energy and enthalpy of mixing. (C) 2018 Elsevier Ltd.