The reaction of the highly polar ion ArH3+ with the nonpolar neutrals Xe, Kr, CH4, CO, NO, O-2, and N-2 and with the polar neutrals SO2, H2O, NH3, CH3I, and C2H5I have been investigated in a selected ion flow drift tube experiment at near thermal conditions. The rate coefficients obtained have typically 15%-35% larger values than the collisional limiting values k(L) and k(ADO) obtained by the Langevin and ADO (average dipole orientation) theory, respectively. These data are explained on the basis of the interaction between the dipole of ArH3+ and the ion-induced dipole and the permanent dipole, respectively, of the neutral reactants. Rate coefficients for the reactions of H-3(+) with the above neutrals were also obtained for comparison, as well as the zero field mobility of ArH3+ in helium being (18.5+/-1.5) cm(2)/V s. The ion KrD3+ (KrH3+) was detected unambiguously for the first time. Its dissociation energy is larger than 0.29 eV which is the lower limit of the dissociation energy of ArH3+.