[en] Inelastic scatterings of 0.8-GeV protons from 40Ar nuclei are analyzed by using an optical potential model in the Dirac coupled channel formalism. A rotational collective model is used to obtain the transition optical potentials for the low-lying excited states of the rotational band. The optical potential parameters of a Woods-Saxon shape and the deformation parameters of the excited states are searched phenomenologically by using the sequential iteration method to reproduce the experimental differential cross-section data. The effect of a multistep process is investigated by including the channel coupling between two excited states in addition to the couplings between the ground state and the excited states. The calculated deformation parameters of the excited states are compared with those obtained by using the nonrelativistic calculations. The results of the Dirac coupled channel calculations are found to show pretty good agreements with the experimental data for the ground state and the low-lying excited states. The multistep excitation process via channel coupling with the second 2+ state is found to be important for the excitation of the 4+ state for inelastic scatterings from deformed 40Ar nuclei.