Dual Mass Flywheels

A dual-mass flywheel (DMF) serves two functions. The primary function is to store energy from each piston’s firing pulse, and then send it to the crankshaft so that it continues smoothly rotating through the next piston stroke. The secondary function is to dampen damaging torsional spikes caused by engine vibration. Historically, the clutch disc services this function, however, complex transmission designs required an entirely new concept, well beyond the capacity of standard clutch disc technology.

Dual-mass flywheels were originally developed to reduce synchronizer wear, gear noise, and chassis rattle in high-torque diesel applications like 7.3L Ford and Dodge 5.9L trucks. However, because dual-mass flywheels were so effective in improving shifting action while reducing noise, vibration, and harshness (NVH), they were soon adapted for use in high-performance applications including Audi TT, BMW 325, Chevy Corvette, and Porsche Boxster. Even more recently, dual-mass flywheels have found their way into more every-day vehicles like Acura TL, Ford Focus, Hyundai Sonata, and Nissan Altima.