Abstract:The lateral self-excited vibration of tread is the root of the tire polygonal wear. The lateral self-excited vibration of tread has been proved to have the character of hard self-vibration by the simulation of the four degree-of-freedom self-excited vibration system of rear suspension in SIMULINK. It is found that the sensitive parameters influencing the self-excited vibration state obviously are mainly the factors of the stiffness and damping coefficient of rubber, vertical load, adhesion coefficient, mass of the tread block, toe-in angle and camber. Then the parameter sensitivity analysis of lateral vibration was conducted to rank the parameters’ influence. At last the main effective measures, including increasing the adhesion coefficient between the tire and road and reducing the toe-in angle, were proposed to restrain the tread self-excited vibration to reduce tread wear.