I have heard some wild ideas that apparently work like pouring a very thick oil inside of doors and of course the normal por 15 or one step spray. I've used the one step spray with decent results in the past.

1.The most visable issues with my truck are the are wrap around skins of one door and the tail gate.

2.The less visable is the frame. I'd like to just spray it or treat it on spot.

3. The biggest issue is my rockers. They aren't rusty at all but I know they rust out from the inside. Is there a way into them to pour something or do I have to drill a hole?

I know some of my ideas may seem crazy to some. If you have any better ideas I'm all ears!

Winters here aren't kind to exposed steel.

 

ttt.

 

Take a look at my post "project rocker repair". I took some pictures and you can see exactly how the rocker panels rust out. Mine only rusted on the flat bottom part, as soon as you rounded the bend, they were solid.

My doors were also bad. I had fixed them earlier. From gutting the door out, and looking inside, I can tell you that the rust is not coming from inside your door. It is only at the seam on the bottom where the outer shell wraps around.
Inside your door will be as clean as the day it was built, unless your bottom is completely gone and has worked it's way up.

As far as dumping paint into your rockers, you can gain access by removing the plastic covers where you step through the door on the inside,or pop out the rubber plugs on the rear towards the frame.

 

i recently bought a 1998 F150, the previous owner used the rubberized oil undercoating sprays (spray can, rubberized is the premium version to the regular oil) on the inside of the box rocker panels. at first i thought they were caked with dirt but i took out a scraper and it was a coating, it had sucked in quite a bit of dirt, so i scraped it all off. the panels were absolutely mint underneath. i'm going to reapply a fresh coat, so that works really well...

 

I actually just sprayed my whole frame today with some rubberized undercoating. Looks like its gonna protect it great. Its thicker than regular spray paint, which i had before. Also has a different texture, kinda like rhino liner but smoother. took 3 cans to cover frame, torsion bars, leaf springs, and gas tank. I dont see how you could beat this stuff.

 

Skizriz, your project was a pretty big repair if I remember the thread correctly, you replaced the rockers! My plan was to fill the rockers with really thick oil but now I'm just going to have the truck Ziebarted. Thanks for the responses guys