Patent ID: 6991583

Claim:
A system for controlling a torque reduction at shifting for an automatic transmission, the system comprising: torque changing means for changing an output torque of a prime mover; shift-state detecting means for detecting a shift state of the automatic transmission shift-controlled by shift control means in accordance with running conditions including a driving state; and torque-reduction control means for reducing, when detecting start of an upshifting by said shift-state detecting means, the output torque by said torque changing means during a period from this detection to completion of the upshifting, characterized in that there arrange actual gear-ratio detecting means for detecting an actual gear ratio out of input rotation and output rotation of the automatic transmission, and torque-reduction amount computing means for calculating a torque-reduction amount out of a torque-reduction set gain set previously, which is a rate of change of the torque-reduction amount with respect to a change in gear ratio, and the detected actual gear ratio.