Leverage

No engineer here, but I've never heard of this being an issue on any of the camping forums I visit.  Logically you would get more leverage with the longer bar but I imagine it has little difference with the thousand+ pounds of instantaneous force you get as you bounce down the road.

D&D - I've wrestled with the question for hours and have come to the following conclusion:

A lever and pivot doesn't increase or decrease the weight of an object.  Instead, the longer moment arm of the lever allows you to spread out (over time) the energy required to move an object.  Instead of a single, quick grunt to raise a rock 10", you could use a lever and fulcrum to spread out the time required to raise the rock and reducing the momentary effort.  By pushing on the free end of the lever and moving it a greater distance (say... 4') you can raise the rock 10" with less momentary energy applied over a longer time.  But, in the end, you expend the same total amount of energy, the rock still weighs the same, and you still raise it 10".

But, setting that explanation aside for a minute: if you look at your trailer tongue and vehicle's hitch, you'll see that there is no fulcrum involved at all*.  Its just a weight sitting on the end of a bar attached to the back of your vehicle.  The tongue weight doesn't change simply because the bar is longer.

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*Technically, this isn't quite true.  Your vehicle's rear axle acts as a fulcrum.  If your goal is to raise your vehicle's front tires off the ground, you could use a very long receiver as a lever; when you add the trailer's tongue weight, the lever and pivot would raise your front tires off the ground.

     Thankyou again, now I understand it a lot better, very good explanations. It is so good to have teachers to explain things so that they can be easily understood. This is another reason why the Rpod owners forum is great for Poders.          David and Danette