We develop a new 3+1 dimensional Monte Carlo cascade solving the kinetic on-shell Boltzmann equations for partons including the inelastic $gg \leftrightarrow ggg$ pQCD processes, where the back reaction channel is treated fully consistently. The cascade is applied to simulate parton evolution and to investigate thermalization of gluons for a central Au+Au collision at RHIC energy. The initial conditions are assumed to be generated by independent minijets with $p_T > p_0=1,3-2$ GeV. It is demonstrated that overall kinetic equilibration is driven mainly by the inelastic processes and is achieved on a scale of $1-2$ fm/c. The further evolution of the expanding gluonic matter then shows almost an ideal hydrodynamical behavior. Full chemical equilibration of the gluons follows on a longer timescale of about $1-3$ fm/c. Also results on the elliptic flow v2 in noncentral collisions will be presented.