Late model Ram 2500 Icon 2.5 VS sku# 217708CP adjustable rear shocks. They have been revalved for a heavier load.
Icon can revalve the shocks for $75 for any load ratting you like.
These were valved for 4,000lbs for a truck bed camper that I used a couple times a year. I would run full soft when I had no load and full hard when the camper was on.
These were $1,600 plus tax new and are a year old with about 10k miles on them.
For stock height suspension.