Never seen it done like that. We would remove and stow wrapper and set the pin on the reach. Load goes up and you back up (only takes an inch or two) to let pin drop in compensator and drive away. Some trailers have a bill hook that latches instead of a pin. That load should not move until the truck leaves and heads over to load the trailer on the truck. That’s a long log trailer, common throughout the western United States and Canada. I wonder where this was.
This might make the compensator easier to understand. It slides in and out - necessary to allow for turning. The logs actually pull the trailer when loaded and the reach only steers the trailer.
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