Rust in the frame rails

[mpace6a]

In the middle of replacing my floors, and I've noticed that every day theres flakes and small pieces of rusted off metal inside the frame rails, and no matter how many times or how long I suck it all out with the shopvac, theres always more the next day. Should I take off the top of the rail and clean/coat the inside of the frame rails too, and if so how do i go about removing the top of the rail with as little cutting as possible?

[87Warrior]

To get that top cap off of the frame rail, you will need several spot weld cutters and a whole lot of patience. You can see how I went about doing the same thing in my '92 build.

[Eagle]

If you remove that top "cap" inside the cab, that won't get you access into the frame rails. The sheet metal floor runs across the top of the rail, then the "cap" is welded on over the floor pan. Where are you seeing rust inside the frame rail? Are you sure it's not just rust from the cap? I don't think you CAN see inside the frame rail.

[mpace6a]

I'll take a pic in a few to show, but theres two round cut outs, one in the front, and one in the back, and i can hold the shop vac hose up to either of them and constantly get more rust flakes and crap sucked out of it almost every day

[87Warrior]

Ah yes. There are access holes to the frame rails through the floor pans under the cap. Removing the cap and floor pan piece will get you access to the frame rails under the cab.