Ron (or anyone else who wants to take a stab at it),
I'm struggling with this and I am going to try and explain where my problem is. Using truck springs as a reference for the affect of weight transfer on a truck with airbags installed, I'm having difficulty with 1 point and hopefully you can give some insight.
If I were to apply a tongue weight to the back of my truck, the back of the truck will go down and the front will go up. Before applying weight distribution, if I raise the back of my truck by 2 inches with airbags, theory says I would raise the front of my truck by 2 inches as well because the truck is still loaded the same way. This may not actually happen because of the spring design but the front should still rise somewhat. Now if I apply my WDH, using the directions, I would return the front of the truck to 50% of it's unhitched height.
Wouldn't you agree that I need to be careful with which unhitched height I use? If I use the unhitched height before air was put in the airbags, I will end up with more weight transferred to the front axle than is recommended. By using the height after air is in the airbags, there will be no noticeable change in the stance unless I use the WDH to transfer more weight to the front.
Now in the case of 93Cobra2771, he also did not change the adjustment of his WDH as stated above when adding airbags but explained that he was setting up his hitch with the updated method of 1/2 way from unhitched. Theoretically, he has the same weight transferred to the front axle, even though now he is setup under the newer method. So he is not really transferring less weight to the front as recommended.
This is why I made the assumption of the reason for the hitch adjustment change but obviously based on the information you provided, it has nothing to do with it and I am stumped.
I guess this is why I am stuck on the ability to achieve a level stance when towing a travel trailer and suggested using it as a tool to stabilize the truck as mentioned in my first post in this thread.
Although not specifically relative to the question, let me explain my real world experience. I tow a trailer with 1200 lb tongue weight with my Ford Excursion. With the kids in the truck, it is weighed down pretty good. When on rough road or bumpy road, the back of the truck could feel a little floaty so I decided to add airbags. The WDH has always been adjusted with the front slightly high because when I set the hitch up, I felt it drove better this way. (It is only a coincidence that the new way was recommending this and was published later). When I put air in the airbags, I raised it until the truck was more level when hitched up, I'm guessing about an inch or 2. I did not notice much front end rise but in the end it did rise a little (I posted a question here a while back and I just looked it up and it turns out you are the one that assured me that it did rise). Anyway, it drove terrible. I adjusted the hitch many different ways and in the end I dropped the air pressure down to a point where I just saw the rear of the truck rise and my ride has become quite comfortable. The back of the truck is real stable and that floaty feeling is gone. My WDH adjustment is exactly what I used before the airbags were added. To me, the addition of the airbags was a success in that I achieved what I wanted, but the OP wants a level stance so I suggested a different approach which you somewhat agreed would be appropriate.
