Sober
IF the package car is empty, there is no problem. IF both are full, there is no problem, there is weight on the front of the tongue.
The problem lies when you have a package car that is loaded, and a trailer that is not, or is loaded only behind the tires.
This puts the ball below the hitch even without the jack being on the ground. This puts a negative pull up-wards for the whole trip. While a properly latched hitch should be able to handle it, they were not designed for that type of lift.
So the question remains, is there something in the DOT regs that address the issue of negative tongue weight on a trailer.
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