In our work we consider the librational dynamics of the chains in paraffin crystals. We consider the paraffin chains being completely rigid and only inter-chain potential is taken into account. To study the possible change in the dynamics with the increase of the temperature, i.e. when the system achieves the vicinity of the rotation phase transition we consider the model without restrictions on the amplitudes of the rotational angles. The nonlinear spectra of the system are studied.