Abstract: Control system for a pressure medium operated clutch (1) and reduction gear unit (4) to qualitatively improve torque reversal gear shifts by measurement of rotational speeds of the gear unit input shaft (41) and the turbine shaft (320) of a torque converter (3) through sensors (51, 52) and determination of differential speed conditions by an electronic unit (5) to which the sensors are connected. Upon displacement of the gear shift lever from neutral to gear drive position, the electronic unit issues a corrective fuel controlling command through line (22) for a length of time sufficient to obtain equality between the turbine speed (Nt) and the gear input speed (Ni) plus a correction factor (AN). The corrective command is applied to a control lever (71) of the engine fuel injection pump (7) through an automatic operating arrangement (90) superimposed on the fuel control linkage (8) connected to the control lever.