Output Shaft Speed (OSS) Sensor
WARNING: This page is about a different car, the 2012 Ford F550 Super Duty and 2012 Ford F450 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
The transmission OSS sensor is located on the extension housing. The OSS sensor is a Hall-effect type sensor. The OSS sensor reads the gear teeth on the park gear, which are different than the teeth used for the park function. The OSS input to the PCM is used for shift scheduling and TCC operation. The OSS sensor has bi-directional capability and has a digital output.