Mine was not missing a sweeper underneath but as we pulled in the slide the slide tips over and comes up about 2-3 inches and the result is about 2.5 inch. The rubber seal was protecting it when it was out but when we pulled in the slide created a huge gap. I could see light inside my FW under the slide when it was in travel mode slides in. The road rain as the tire spinning brought the rain water through the gap under the slide and ended up on my kitchen floor. It was a bad design and the factory overlooked this problem. I fixed numerous things like lose moldings, kinked pipes, insulation in the underbelly the list is too long. Ones I fixed all that than we traded it in for a MH. Now I'm fixing everything on that. I always find a way to make something better.
There is no standards in the RV business so the RV MF can sell any junk for a big bucks. The dealers will not fix anything which was not originally included in the RV. I'm sure most of you know all this already. No RV is perfect.