Harsh ride from rear end over cattle guards and expansion joints, solution?

I have a 2013 Baja TX running stock springs and dampers and 81k miles on the clock. I do a lot of high speed off road driving (50-70 MPH) on dirt roads in the oil field and I find that when I hit bumps like cattle guards, or expansion cracks in bridges, where both rear tires hit at the same time, I get a very harsh bump from the rear end. I have a topper and tend to always have 300-400 lbs of stuff in the truck, so right after I got it, I installed a set of Firestone Ride-Rite air bags, and I usually run 5 lbs if of pressure in them. They do a good job of dealing with the sag in the rear end, but I am wonder if they are contributing to this harshness.

Any suggestions on solutions? I need the topper, and I have to carry this weight with me all the time, so I need something that will let me keep up the 60-70 MPH speed, but not hammer me every time I hit a cattle guard. Do I need upgrade rear leafs, hydraulic bump stops in the rear, both? Suggestions would be greatly appreciated.

 

Well I can't help you alot but I do know those ride rites aren't supposed to be used while off roading it's a good way to blow up those bags. other than that I don't have advice for you but maybe put some kings in the back smooth body kings would work alot better than stock

 

With that weight you should upgrade to Dakars and better shocks

 

New leafs and shocks.

 

So are Dakars the only real option for solving this problem that will give me around 2" of lift over the stock off-road? The Bilstein 5160's that came on the Baja are pretty decent shock and still appear to be in decent shape.