This is complex. The longer "moment arm" being provided by an extended ball mount will change the forces of torque applied being applied at the rear of truck, far behind it's natural front to back 'balance point' and also much further behind the rear axle.
A longer ball mount arm will greatly increase tendency to unload the front axle and overload the rear axle, in comparison to your current axle loads while towing. That imbalance might be addressable by adding WDH, but only if your truck hitch and its attachment are strong enough to handle al the added torque forces. I would not be inclined to abusing any truck hitch assembly in this way (a ball mount arm longer than 24"), unless it was rated for at least 10,000 "towing capacity" with the use of a normal-length ball mount.
The hitch ball weight for a properly loaded TM is at least 350 lbs. (TM "officially" allows Tow Vehicles which are rated for only 3500 lbs trailer weight, and the TV manufacturers are assuming 10% hitch loading to be safe when they supply those numbers.)
In practice, though, better control of the trailer will likely be obtained with more than 10% of Trailer Gross Loaded Weight on the hitch. The trailer becomes much less likely to "drive itself" into skids. My own 2619 loaded 'heavy', has about 440 lbs gross weight at the A-frame hitch ball mount receiver, before applying WDH forces at that joint.
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In every normal TM towing al SUV and Truck, however, the receiver for the the hitch ball mount as at the rear of the vehicle is already behind the rear axle by a significant distance. The overhang of the hitch ball mount receiver added to the a normal ball mount length of 6-10" creates torque on the receiver: The resulting torque forces cause the rear axles to squat down more, and the front axle of the TV to be lifted.
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The situation is complex than that, because the Truck's hitch assembly is not really the fulcrum. When the Hitch Assembly can remain unbroken (that's very desirable
) the truck or SUV actually resists the twist with its own body weight,and the new weight loaded on the two axles. Because the balance point is shifted towards the rear of the truck, the rear axle carries more weight, and the front axle wil carry a smaller portion than before. That can affect braking and steering control, making the TM more likely to break lose and skid (driving itself).
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Before switching to a dramatically longer hitch ball mount, you should make a careful assessment of the hitch assembly on your truck. It will need to be very strong, because you will require it to resist much higher twisting forces at the ball mount receiver (without cracking or coming loose).
The issue of truck front axle 'unloading' versus rear axle 'higher loading' might require the addition of a WDH, even with a truck, and even though the forces applied by the WDH will tend to make further increase forces at the the truck's hitch ball mount of receiver. and its frame attachment.