Abstract: A multi-lobed gear system is provided in which the lobes of an input gear and a corresponding, mating pair of lobes in an output gear are uniformly in contact. The lobed gear tooth profile of the present invention reduces material galling, shuttering and whipping within a drivetrain assembly in comparison to square or helical splines that incorporate single point contacts between meshed pairs. An internal pinion gear or slip yoke internal shaft employs a lobed gear tooth profile that forms a sinusoidal outer perimeter shape. The perimeter surface is in constant contact with the complementary shaft or gear across its entire surface. A small clearance gap may be provided for lubrication, fitment and manufacturing considerations.