Abstract: The loading system developed can be used either indoor to simulate a torsional load or to duplicate an actual drawbar load in the field. Utilizing the system, sinusoidal load, saw-tooth load, load spectrum and actual load obtained when a tractor was being operated in the field were simulated. It is shown by χ² examination that the distribution of all simulated load curves accords with that of their sample curves under level 0. 05.