The underside of my 04 SCREW is covered with rust. I bought it new and have always tried to take pretty good care of it. It currently has 92K miles so it has sat dormant a lot of it's life. (maybe that has contributed to the issue). It has been on the beach twice in it's life and that was years ago. Here in VA we get some snow so it has seen a little road salt but not an extreme amount. I have noticed for years that everything underneath was covered with surface rust. I mean everything, springs, axles, suspension, steering everything. Now that's just surface rust that isn't hurting anything but still I have always thought that was weird. Had it on a lift the other day and checked it out thoroughly underneath and damn if the bed isn't about to rust through. From the topside everything looks pristine but the bed cross members are all rusted where the meet the bed floor. and where they attach to the frame. The seams in the bed floor are all rusted as well. Nothing at all is visible from up top but If I had a load of rock or something heavy I would not be surprised to see holes come in it it's so bad. No rust in the rockers of lower cab corners that is often typical either.
It's too far gone now to do anything with but replace the bed when it gets that bad but I just feel it's weird for it to do that. I have a friend that works at Carmax and he said the 04s were plagued with that issue but I have never heard it mentioned elsewhere.
Just curious if I am just having bad luck or is anyone else ever had that issue?

 

You live on the edge of the rust belt and moisture gets trapped in the places you're seeing rust. These trucks weren't designed by Ford to survive 20 years in the rust belt area, unfortunately. It sucks, but it happens. My '06 has been a Colorado truck it's entire life - we don't have nearly the rust issues as you do but I'm starting to get bubbles in the cab corners. It's simply a matter of when, not if, rust will eventually take over. If anything, you're lucky it's in the bed, not the cab corners.

Be glad you didn't buy a Tacoma - those frames rust out in as little as 4 years, depending on where you live. It was so bad Toyota did a massive frame replacement program and replaced hundreds of thousands of frames at their cost. This was for '97 and newer Tacomas. Those that got replacement frames 5-10 years ago are already rusting through again.

I'd take a rusted out bed before a rusted out frame any day. Not much you can do for the bed it sounds like, but you can definitely clean and treat the frame.

 

Go PG Royals! Hey, I'm right down the road from you and I agree, with limited driving in the salty slush, no car around here should rust out. My '07 has basically none and it has 30,500 miles. So it sits a lot but it sits on pavement that drains well. If your truck sits on the ground or unpaved stone, it is a much different situation.
You can take a pump yard sprayer, mix up some water and most any rust remover and spray the whole underside. It kills it and leaves a phosphate finish. You might have to do it a few times but it really works. It also forms a good foundation for paint.

 

In 2015 I traded in my '04 because of the rust and corrosion on everything on the underside. Over the time I had it I replaced most of the solid tubing, had the bracket for the center bearing on the driveshaft rust through and fail, and even had the tail shaft housing on the transmission leak because of corrosion. The frame had surface rust, but was still solid. From the top it looked to be in great shape and it still ran strong, but 11 New England winters took their toll.

 

I live west of you, my '07 has this patina on the driveshaft and I think the transmission mount maybe?