Input Shaft Cutaway View
WARNING: This page is about a different car, the 2018 Lincoln MKC. However, it is still accessible from the selected car via links, so may be relevant.
Input Shaft
The input shaft is part of the direct/overdrive clutch assembly and is splined to the torque converter turbine and the center planetary sun gear. The input shaft transfers power from the torque converter to the rear planetary gearset through the center planetary sun gear and the direct (3, 5, R) and overdrive (4, 5, 6) clutches.