I have had two trucks very similar to yours. With a TC probably 500 to 700 pds lighter. I have used on both those trucks quick disconnect torklift's on the lower springs and have been very happy with the results. My max is around 3600 pounds as wet as can be and my current 2017 chevy 3500 srw handles very good with the quick disconnects. My truck handles reasonably good without them but there is a definite improvement with the quick disconnects engaged.
I don't know how to read the dust lines but once you get your rig fully loaded and go on a few trips I think you will notice two much sway on corners and to much coming close to bottoming out without some additional support with as much weight at you will be hauling.
JMHO
