Vibratech TVD invented viscous damper technology in
1946. Since then, the design has been imitated but never
duplicated. Fluid filled Vibratech TVD dampers are used
by the largest names in diesel engine manufacturing for the
following reasons: Quality, Dependability, and Longevity.The Vibratech TVD viscous torsional damper is a design that consists of a free rotation inertia ring surrounded by a viscous silicone fluid enclosed in a laser welded, sealed housing.

When crankshaft torsional vibrations occur, the outer housing of the damper reacts with the crankshaft, twisting as it rotates, while the inertia ring attempts to rotate at a constant speed. This relative motion between the inertia ring and housing causes the inertia ring to shear the silicone fluid, which reduces the destructive torsional vibrations of the crankshaft. When left unchecked, these vibrations may lead to a cracked or broken crankshaft, valve train problems and premature bearing wear.