Engine crankshafts experience torsional vibration. This vibration can cause noise, wear, and crankshaft failure. For cases with large torsional vibration, an elastomeric torsional damper can be used to reduce the crankshaft vibration amplitude. In some high horsepower engines, the torsional vibration amplitude is too large to be attenuated by an ordinary elastomeric damper in the available space envelope. A practical solution to this problem is a dual frequency damper. A dual frequency damper is essentially two torsional dampers acting in parallel. Our tests show that a dual frequency damper, with less combined inertia, can outperform a simple single frequency damper.