Saw this on Big Rigs.
Surely this idea was dumped years ago as it transferred weight to the Ringfeder.
Brother in law had one and was defected. Transport dept would only allow them if used with a Barrett ball.
Not going to pull road train loads through a ball.
That's true but there will always be a reaction from braking and the actual towing load.
If the dolly is up front of a road train there's considerable reaction just getting it all moving, not to mention uneven road surfaces, creek crossings etc.
Looks great for smooth highway work.
Their argument seems to be cost of this V's a triple dolly as both track better than a tandem dolly with conventional drawbar.
Lots of input from old timers who say these things fell to bits on the rough stuff.