A plastic spring having a corrugated tubular body with connection surfaces at its ends for transmitting force between two structural component parts which are movable relative to one another. A connection surface of the plastic spring is constructed as a tubular body which engages in a cup element of one of the supporting structural component parts. The cup element can be filled with a displacement mass, and the tubular body accordingly carries out a displacing movement within the cup element for axially adjusting the preloading of the plastic spring.