Aluminum corrosion

[tstrickland]

It was worth a try 🥴 This is the only place I’ve seen anything posted about what we have going on, which is the same as him but only on one slide.

[JRTJH]

Look under your trailer, at the back surface of where the corrosion is occurring. I think you'll probably find some "water holding piece" behind the J-wrap. I'd guess Keystone may have used some wood or a wood product like OSB as a backer to stiffen the aluminum panel to keep it from flexing or bending. If that wooden product gets wet enough to become saturated with water, it sets up a perfect condition for aluminum corrosion to begin.

Another possibility is galvanic corrosion which occurs when two different types of metal are in contact with each other. When they get wet, it sets up a small "electric difference" between the two metals and as electrons flow between them, corrosion begins. That is one of Ford's biggest issues with the aluminum body panels on a steel frame with steel stiffners holding the aluminum in place.

You may find the answer to "why" by looking behind the corrosion to see what's there. The "how to fix it is to cut out the corrosion and patch the panel (scab patch) or to just bite the bullet and replace the entire panel.