Procedure for operating decelerating downshifts with the participation of a form-locking shift element of an automatic transmission comprising a torque converter lockup clutch

摘要

A method of carrying out coasting downshifts that involve an interlocking shifting element in an automatic transmission having a torque converter lockup clutch. At the beginning of the coasting downshift, positive action is taken on the torque. The method including the steps of, at the beginning of the coasting downshift, the torque converter lockup clutch is fully or partially disengaged so that the drive-train is fully or partially decoupled from the drive aggregate, and action upon the torque is carried out in such manner that the engine rotational speed only falls below the turbine rotational speed once the synchronous point for the interlocking shifting element is reached.