Interesting. Same thing is happening to ours on one side. We will be taking back to dealer for fix after we are done using it for the season. Will keep you posted on what they do. Since it is multiple colors, just re-caulking with one color isn't an acceptable fix to me. I also want to know why it's cracking and make sure that something connecting the cab to the actual coach is not loose.
I believe it cracks because the fairing is attached to the cab which is made by Ford and the coach body which is made by FR. The isolators are dissimilar which would cause a differential in movement of the two parts. Repainting will make it look pretty until you head down the fine roads we have. A nice drive through Indy on I-70 should take care of it. Good luck.
FYI: Back before vehicles had stiff bodys they used welting between the flexible parts, never painted.
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