TRANSMISSION SYSTEM FOR VEHICLE

A transmission system for vehicle includes a clutch (3) disposed in a power transmission path (6) between an engine (2) and a vehicle wheel (5), a transmission (4) disposed in the power transmission path (6), a clutch actuator (11), a shift actuator (13), a vehicle wheel speed sensor (16), a sudden deceleration detecting unit (S1) that detects a sudden deceleration of the vehicle wheel (5) based on an output signal of the vehicle wheel speed sensor (16), and a shift control unit (10). The shift control unit (10) executes an ordinary shift control (S2 to S9) to shift to a speed adaptive shift stage associated with the rotational speed and to execute, when the sudden deceleration detecting unit (S1) detects the sudden deceleration of the vehicle wheel (5), a sudden deceleration adaptive shift control (S10 to S19)to shift to a shift stage lower than an actual shift stage at the point of detection of the sudden deceleration and higher than the speed adaptive shift stage associated with the rotational speed.