[1retired06]

Cracks along the slides do happen, and I experienced a serious split on my 2005. I am surprised it is just showing up on your 2004 model after so many years. On my 2005, it started right away, and the dealer reinforced the frame, and the problem did not reoccur. Specifically, they welded a reinforcement brace at the frame underneath the slideout, and then did the necessary bodywork. It did require a cut and patch to get to the frame. I also had minor cracking on my 2002, but it was just on the surface, and I cosmetically fixed it with a thin bead of caulk to keep the moisture out, and had no further problems. Hopefully yours is not structural but just cosmetic aging.