My 2000 7.3 EX has a little bit of a hard time with 6400 lbs in the back cargo area. Currently have stock springs with one leaf added and Firestone airbags. Need to upgrade before something goes wrong. Has anyone used F 350 springs on their 2wd EX? I know where i can get some off a 2005 dually. (not sure what spring code, but is has to be better!)
Also going planning to 14 ply tires and a rear sway bar.

 

It's been done, but you'd also need to level up the front with the rear...

My springs were more than sagging in 2007 and after much research, went with a full 6 inch lift kit. That's overkill for your situation, but the point I'm trying to make is that it's not easy to mod the suspension on a 2wd without going to a lift kit.

If I'm not mistaken (which I've been known to be) it sounds like you're exceeding the payload capacity. To be clear, are you towing a trailer or loading up the second and third row?

 

To clarify, the 6400 lbs is loaded in rear from 2nd row seat to backdoors. So not only do I exceed payload (by a lot) Its in a bad place too. For right now, this vehicle HAS to do this job, so I have to make do with what I have .

 

With that much weight you're on the rear bumpstops for sure, even with the bags. It must drive like a tank, makes my back hurt just thinkin' about it. Good thing there's a full floater axle. What'ya hauling, ingots?

 

With 100 lbs in the air bags and the extra leaf, no bumpstops yet,,, but it does drive like ***...