Equations of motion with six degrees of freedom are composed of detailed dimensions of vehicle, suspension, steering and tire, which must be determined at the designing stage. Particularly, in the dyamics of suspension system, the hypothesis of fixed roll axis are excluded. And, instead, the effect of side force which affects rolling and vertical motion of the vehicle is introduced on the basis of geometrical variation of the tire's contact points. In addition, a number of equations including the cornering force of tire are treated in nonlinear method, with the effect of driving and braking forces being taken into account at the same time. This analysis has enabled strict interpretation of cornering characteristics. However this article is devoted mainly to the analysis of various phenomena which take place in critical situations responsible for accidents in cornering, resultant from spin-out, drift-out, wheel-lift (jack-up) and roll-over. The results of computations and experiments are always correlated for the study of suspension specifications, friction coefficient of road, and effects of driving and braking forces.