So a lot of people have offered to spend $500-60,000 of your money in attempt to solve your problem on guesses. While many of those things tend to improve from whatever you have now, no one can find the root cause of the problem yet. I recommend starting with scaled weights as some have mentioned. With that you can find out how much TW amount and % you have, how well your WDH is adjusted, and where those weights stand with respect to all your truck's ratings.
cobra98 wrote:
The stock wheel well measurements of the truck are 38.5" rear and 37" front. After install and trailer hooked up with WD it's 36" all the way around. Dropped 1" in the front and 2.5" in the back. Trailer is level.
If those are accurate, I suspect you have have far too much TW as well as improperly adjusted WDH. Most half tons with 800-1000 pounds of loaded TW and the WDH adjusted to return front axle to unhitched height leaves the rear to settle about 1.5" lower than unhitched. But some scaled weights would be better before spending any money on random upgrades to the truck.