RecurDyn/DriveTrain supports many functionalities so that user can make transmission system composed of shaft, bearings and gears. In the case of shaft, it is made of fflex beam with various cross sections. User can control length and radius of arbitrary cross section. Additionally, element size and property of flexible body can be adjusted in the shaft modeler. In the case of bearing, user can specify bearing geometry and property by direct input in the bearing property dialog. Additionally, RecurDyn provides many bearing libraries including bearing speciofications used in many engineering fields. In the case of gear, user can specify gear pair geometry and material by direct parameter input related to it. Also, z12 module file, which KISSsoft provides, can be used in order to specify gear pair geometry. To do this, RecurDyn provides the ability to run KISSsoft GUI. Finally, RecurDyn provides the ability to take advantage of its own involute gear contact solver.