I bent mine the first time when I went through the whoops too fast and almost endoed several times in a rod (looking at the ground floored in 4WD hoping the bumper wouldn't catch). Anyway, it bent the frame pretty bad, bed was all out of alignment with the cab. Before that the bed wasn't touching the frame and it was aligned perfectly. Then I got the frame bent back to factory specs on a hydraulic frame machine, and the bed was once again with a gap between the rails and the frame.
Well now, from regular wheeling and duning, nothing out of control but I guess not whimpy either, the frame is bent and it is touching again. It wasn't from weight, it was from impacts at speed. The axle is trying to go up and the bed is trying to go down and something has to give, and the 1/2 ton frame is apparently weaker than a 14BFF. I can see where mine bent right where the factory bends are.
If you have one of those digital levels the rear portion of the frame should be the exact same angle as the front. If that is true then you are probably fine. Another way to check is take an 8 foot level or straight edge, when mine was bent bad the bed was bowed up in the middle, not flat/straight from front to back. If its just barely touching the bed will still be straight still. If you can check that maybe it will make you feel better. Sorry , didn't mean to scare you. It just seems like your truck is used similar to mine with similar suspension (coilover front leaf rear) and so it appeared you might have the same problem I did. But I also weakened mine the first time I bent it when I almost flipped.
