This study aims to incorporate the dynamic stiffness of pads into the finite element method (FEM) used for brake design in order to improve the accuracy of FEM analyses. In the first step, the vibration caused by a disk brake squeal is simulated in order to measure the dynamic stiffness of the brake pads. We then compare this result with the static stiffness result obtained from a past static compressive strain and show that these different modes of stiffness have different characteristics. The dynamic stiffness of the pad is higher than the static stiffness and is greatly dependent on pressure load. The next step is to show, from the squeal experiments using a simple squeal tester and FEM analysis, that it is dynamic stiffness and not static stiffness of the pads that correlates to squeal. Finally, the aim is to demonstrate that by incorporating the change in the dynamic stiffness of pads resulting from wear into FEM analysis, the change in the frequency of squeal attributable to wear can be reproduced.