The purpose of this study was to analyse the dynamic behavior of a tractor driveline with respect to torsional vibrations in order to improve design procedures for transmission quality. A model of the transmission line was developed by CEMAGREF and ENSAM for the RENAULT 145-14 TX tractor. The model was tested by comparing the global torsional stiffness of the model to experimental measurements of the actual stiffness for different gears. Then, the natural frequencies of vibration of the model were determined and checked against the frequency of the vibrations generated by the engine to detect any detrimental coupling. The results of this investigation are presented in this paper.