A torsional vibration isolator coupling displaying particular utility in automotive vehicles powered by internal combustion engines of the diesel or otto type. An input torque shaft having undesirable torsional vibrations, such as a torque directly derived from an internal combustion engine, is coupled to an input torque disc. The periphery of the input torque disc is coupled by an elastomer member and an intermediate rigid disc member to the periphery of a torque output disc, the periphery of the latter also carrying an elastomer member. The two torque discs are parallel and coaxial. A torque output shaft is carried by the torque output disc. A rigid cylindrical retainer axially clamps and axially compresses the elastomer members against their sandwiched torque discs. The output torque is substantially free of torsional vibrations, thus extending the life of power brake, power steering, and the like units driven by the torque output shaft.