Slider lateral stiffness and damping coefficient between the machine tool subassemblies are identified in this work. First, the physical parameters (such as moment of inertia of mass) are obtained from the system. Next, the rigid body modes of the machine tool subassemblies and its natural frequencies are found by experimental modal analysis. Finally, the stiffness between cast parts in a subassembly can be identified by substituting the natural frequencies and physical parameters into the corresponding equation of motion. The method developed in this work are applied to an experimental rig and to identify the stiffness of interfaces between moving parts of a machine tool.