All transmissions have two major parts: the gearbox as well as the torque converter (or in the case of a manual transmission, a clutch). The gearbox is responsible for in fact switching the gears, although the torque converter helps you to transfer the power from your motor towards the gearbox. https://zanderxcayx.bloguerosa.com/33076642/the-5-second-trick-for-filter-gearbox