Vibrations in vehicle brake systems have been subject to research for a long time. One simple phenomenological model ist the classical friction oscillator, consisting of a mass on a belt. A closer look to a real brake system reveals that from the tyre's contact on the street to the disc the brake torque is transmitted via the tyre, which also possesses elastic, dissipative and inertial properties. Motivated by this fact an extended 2-DOF friction oscillator model is developed featuring the

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... inertia and the dissipative and elastic behaviour of the tyre. In this article the model is given and simulation results are presented. By means of spectral density analysis these data are examined and it is found, that additional torsional elasticity und damping can induce very low frequent vibrations in the regime of low driving velocities, that cannot be observed using the classical mass-on-a-belt-model. An analytical stability analysis of the steady state is performed and stability maps over system parameters and the friction characteristic's slope are given. In addition an outlook on further studies is given.