In this paper, a transient finite element analysis method is used for application to the simulation model to reproduce hot judder phenomenon. A Disc, pad and cylinder are created by three dimensional finite element models. Each part is connected by joint and rotational velocity is applied to the disc. In order to generate convective heat transfer on the surfaces of the disc, the external temperature is set to 20 degree and initial temperature of disc is set to 160 degree. And then friction energy is generated by contact between the disc and pad. This energy is converted into heat flux and temperature of the disc is changed. Under this process, temperature of the disc rises and disc thickness variation is generated. In this study, temperature and disc thickness variation of an existing disc and results of a modified disc which is applied to initial disc thickness variation are compared. The reliability of the modified disc is verified.