Lysholm-Smith torques converters has a special importance, due to the fact that this kind of machine can realize a continuously variation of the torque and of the rotational speed to the outlet shaft as function of the resistant torque and, in the same time, an amortization of the shocks and vibrations. This type of torque converter has three turbine stages, intercalated by two stages of reactors (having stationary blades). The present paper presents theoretical and experimental results obtained on a Lysholm-Smith torque converter CHC-380 in the laboratory of Hydraulic Machinery Department from “POLITEHNICA” University of Timişoara, ROMÂNIA. Theoretical, was studied the behavior of the torque converter, expressed by the characteristic curves. Experimentally, was studied the variation of the temperature inside the torque converter with and without the cooling system and, also, the influence of the filling degree on the characteristic curves. The paper discusses, in the same time the definition and the variation of the degree of transparency for this particular torque converter.