Numerical and experimental studies are performed to investigate the effect of the underbody shape of the simplified road vehicle on drag and life. Four different vehicle models with front and rear slanted variations at the lower surface are used in this study. Cases with a slanted underbody surface at front have smaller drag than those without a slanted surface. Also, cases with a slanted underbody surface at rear have smaller lift than those without a slanted surface. Pressure distributions along the model surfaces and velocity fields at the wake region are examined in detail. In general, numerical solutions are in agreement with experimental results.