Provided are drill stem assemblies with ultra-low friction coatings for subterraneous drilling operations. In one form, the coated drill stem assemblies for subterraneous rotary drilling operations include a body assembly with an exposed outer surface including a drill string coupled to a bottom hole assembly, a coiled tubing coupled to a bottom hole assembly, or a casing string coupled to a bottom hole assembly and an ultra-low friction coating on at least a portion of the exposed outer surface of the body assembly, hardbanding on at least a portion of the exposed outer surface of the body assembly, an ultra-low friction coating on at least a portion of the hardbanding, wherein the ultra-low friction coating comprises one or more ultra-low friction layers, and one or more buttering layers interposed between the hardbanding and the ultra-low friction coating. The coated drill stem assemblies disclosed herein provide for reduced friction, vibration (stick-slip and torsional), abrasion, and wear during straight hole or directional drilling to allow for improved rates of penetration and enable ultra-extended reach drilling with existing top drives.