Thanks for all the helpful input. The receiver has a sticker that says max load 10,000lbs and max tongue load 1,000lbs and then says to check the owner's manual for more information.
The owner's manual says what I said before 9,100lb towing, max tongue 910lbs and GCVWR 15,100lbs. Only requirement is the Nissan tow package which I have. There is no mention of any of the ratings being dependent on a WDH.
I can't connect the trailer and measure front end lift or trailer drop or anything like that since as soon as I connect the trailer the vehicle automatically inflates the airbags to level the Armada. So once the pump cuts off the vehicle is back to the same level plane as it was before connecting the trailer.
Since a WDH will not make any difference as to the Armada/s "levelness" and I already have a Husky Dual Pad Friction Sway Control device I'm not sure what the WDH would do. I mean the vehicle and trailer will be sitting level before even connecting the torsion bars. If I connect the bars and raise the rear of the Armada above level that doesn't really seem like a good idea.
Thanks for all the info and especially the real world experience. I guess I'll be doing a little more research over the next couple of days. I have no problem spending the $ for a WDH but I would like to avoid the hassle if I can.
And I know actual weights are not the same as published weights. It's just that I don't happen to own anything to weigh with right now so I have to make a few assumptions.