Very few half ton owners towing 8k pound dry TTs are happy. Even fewer of them are Ram half ton owners. The 2009+ suspensions are just very soft. Confirm your as equipped payload as I have never seen or heard of an owner of a 2009+ Ram with 1600 pounds of payload. 1200-1400 is more common, and some under 1000 pounds.
700 pounds of TW for 9k loaded TT will not be comfortable over 50mph. It will sway too much. 9k loaded should have more like 1150 pounds. Boats can get away with much lower percentage of TW than high walled trailers.
No vehicle manufacturer in the last 10 years has recommended adjusting a WDH to restore more than 100 percent of the front axle lost weight, such the 20/20 percents of TW carried by the front axle as camp-n-family mentioned. Consult your vehicle owners manual for details. Restoring all the lost front axle weight with a WDH will typically put 80 percent of TW on the TV rear axles and 20 on the trailer axles.