Power section and transmission components within a downhole drilling motor that may reduce or eliminate axial thrust loads on the transmission of the drilling motor are provided. The transmission may utilize a driven shaft coupled between two connectors that enable torque transfer to and from the transmission while allowing the driven shaft to move freely in two planes. The power section may include a rotor with a through bore and a flex-shaft disposed in the through bore. The flex-shaft may be designed to rotate with the rotor. The flex-shaft may extend beyond the length of the rotor in one direction to be centralized within a bearing assembly. The opposite end of the flex-shaft may include a load-carrying shoulder that is retained in the bottom end of the rotor.