Abstract
The paper analyses the influence of non-linearities induced by the clearance elastic link of caterpillar tractor coupling devices on the dynamic stress in tractor transmissions, for the starting and acceleration of the tractor - implement system. For this purpose mathematical modeling has been conducted, of the tractor - implement clearance coupling, using the mathematical model of the torsional vibrations of the transmission system. Further the paper presents the results of theoretical research based on computer aided simulation, in relation to the dynamic stress in the coupling device.