I just purchased a 1995 as a project truck and let me tell you, there is more of my frame missing than is there. I'm 55 and have been in the business since age 15, first as an auto body tech (one of the FEW in CT to actually get a journeyman's cert in it....).
Been to Chief Ezy-liner school, Car-o-Liner school, went on to become a trained coach builder, working on border patrol trucks for Kuwait as well as President Marco's Limo.... then in 1988 started my own business
www.ccrbike.com. So yea, I've got a bit of experience in this stuff. I have two friends who recently purchased new trucks, both over $55K
I will be giving both trucks the treatment that I describe below on them. New trucks don't have ANY rust proofing in the doors, rocker panels and inside areas of the fenders and quarters that trap dirt and moisture. Take your door skins for example, where the skin gets crimped and spot welded over the door frame on the bottom you've got 1/2 a coat of the cheapest CRAP primer that the factory can put in there, and that's it. I just did my buds Ford F350 Econoline van, the bottom 1/3rd of the truck was missing, rotted away with `120,000 miles on it. The engine ran perfect. Ford doesn't put ANY rust proofing between the inner wheel wells and the van quarter panels, or between the door skins and the door frame. There are two things you can do.....
First, get some rust inhibitor....I'll just use SEM brand as an example
https://www.ebay.com/sch/sis.html?_...rosion+Inhibitor+Flat+Black+1+Gallon+Ea+38091 but there are other good ones out there too. take 1/4 inch drill and drill a hole in the inner door jamb and spray some of this in there. It is **** thin, it's meant to get INTO the cracks where rust starts. After the first coat dries, give it another coat. From that point you can either go the Ziebart route or buy what's called "cavity wax" (same stuff) from NAPA.... and do it yourself. When done take acid brush and coat edge of the hole you drilled and let dry and pop plastic cap in there (same as Ziebart does). To the poster who thinks that the factory does a "good enough" job on rust preventative measures you could not be further from the truth.