A further investigation of a pneumatic tire vehicle is performed. The model used is a four wheel pneumatic tire vehicle given by Saibel and Tsao. (24) It consists of a main system, the car body, together with four small subsystems, the wheels. It gives a dynamic system of ten degrees of freedom (4 tire deflections, 4 spring-shock absorber deflections, the roll angle, and the pitch angle of the car body). Tire-force equations are presented. This nonlinear dynamic system may be used to study the behavior of the vehicle under any transient inputs. In the present investigation, a controlled cornering on flat and sinusoidal road surfaces is given. The characteristics of tire deflections and spring-shock absorber deflections and skidding conditions are examined.