F-1 One-Way Clutch
WARNING: This page is about a different car, the 2006 Mercury Milan, 2006 Lincoln Zephyr, and 2006 Ford Fusion. However, it is still accessible from the selected car via links, so may be relevant.
The Fl one-way clutch locks the counterclockwise rotation of the rear planetary carrier during 1st gear operation (during both normal operation and engine braking).