A newly developed finite-difference solution method TUMMAC-VII is applied to the flow about a road vehicle. It is a time-marching solution method for the Navier-Stokes equation in the framework of a fixed rectangular coordinate system. The no-slip boundary conditions are implemented in the body boundary cells. The use of a subgrid-scale turbulence model enables us to resolve the structure of the 3D vortical flows past road vehicles. Simulation is performed for the Ahmed model as well as the GEOSTORM model with a quarter and a half-million grid points, respectively, and the results are compared with experimental results.