That's pretty much the crux of my question- does lightening (or loading in your case) of the front axle count towards pin weight?
I don't understand why everyone keeps worrying about axle weights when trying to figure pin weight. The weight of the truck is same with or without the fifth hitched to it. The only difference with the fifth hooked is the weight exerted by the fifth. THE WEIGHT OF THE TRUCK HAS NOT CHANGED.
Moving the hitch forward of the axle orck of the axle may change the pin weight but it will not change the weight of the truck.
How about we get a scale that does each tire separately? That should start a thread about 1000 pages long to figure out how much a truck weighs.
If one is concerned about overloading axles that is another story but the physical weight of the truck does not change by adding or subtracting loads to it.