In the TM Tire Model, we altered the tread model with the aim of improving the cornering stiffness approximation accuracy for a wide range of tire sizes. The altered tread model made it possible to identify the tread stiffness with a value closer to that of a more realistic tire. However, the altered of the tread model not only improved the identification accuracy of the tread part, but also affected the approximation accuracy of the belt part and sidewall part. We considered the effect of the altered of the tread model on the accuracy of identification of the belt and side parts, and verified the effect on the calculation accuracy of the vehicle motion characteristics.