Title just about says it all. Very surprised to see in my mirror the top of the slide tip out about 3" and then seat itself as I straightened out. We were still on the entrance ramp to the expressway and there was plenty of shoulder to park on. Ran the slides out and back in, could not see any problems with it closing. Instead of taking it to storage yard I went to dealership instead. I explained the situation and was told there is nothing securing the slides at the top. He explained a brace can be added to the top, my expense, to keep it from tipping out during travel. I mentioned that's one way to solve the issue, but it doesn't really fix the problem. Why did this happen now, its been fine for 2 1/2 years? Just happens with age & travel? Have I just missed this and its been happening when I haven't been looking in the mirror? Comments and your experiences please.