When free driving mode is activated, the vehicle bounces up and down. Body parts could become trapped if they are between the vehicle body and the tyres or underneath the vehicle.
When free driving mode is activated, the vehicle moves up and down. Vehicle parts may be damaged if the underbody bottoms out.
Rocking free mode is a function of the suspension which can assist the driver on loose surfaces (e.g. sand, snow) when freeing a vehicle which has become stuck.
The vehicle body rocks in slow, vertical motions when recovery mode has been activated. This temporarily puts the wheels under greater load, which means they have increased traction and the vehicle is freed.
You can activate free driving mode via Off-road Assist More.