The invention relates to a vibration damping system for a motor vehicle transmission, comprising: a support member (1) capable of being driven rotationally around an axis X and having a plurality of outer raceways (16); and a plurality of pendulum flyweights (2) distributed circumferentially around the axis X; each of the pendulum flyweights (2) being mounted oscillatingly with respect to the support member (1) by means of two rolling bodies (12, 13) that interact respectively with one and the other of the two inner raceways (14, 15) of the pendulum flyweight (2) and each interact with one of the outer raceways (16) of the support member (1), the outer raceways (16) being juxtaposed one after another continuously around the axis X, so that the rolling bodies (12, 13) are each capable of passing freely from a first outer raceway (16) to a second outer raceway (16).