Dynamic interaction between railway car and track on a switch and a crossing of a standard turnout is considered. Wheel/rail forces and vehicle motion for nominal track geometric parameters and the influence of the selected parameters deviations on the system dynamic behaviour are considered. Results of computer simulations were compared to proper measurements of wheel/rail lateral and vertical forces during the turnout passage. They imply a conclusion that specific turnout parameters and analysed deviations of some of them create a vital cause of the dynamic interaction growth between vehicle and track.