I was an RV Transporter and had a Ford F350 dually. I added the Firestone Ride Rite with the onboard compressor with the cab mounted control head.
It allowed me to transport the heaviest fivers and goose necks.
When empty, it was also fun to raise and lower the left then right side of the bed or cause both to go up and down while stopped at raffic lights. It was always grat to watch the expresions in the car behind me.
If you gop for it, make sure to get a separate controller for each side. If the pressure is equalized on both sides, then when making curves, all the air will flow to the opposite bag and that makes for a suddenly dangerous sway.
When asked by the cute televison reporter why he had shot a bank robber 6 times with his .45, the Texas Ranger replied, "because they don't make a .50"