I have a 2007 Itasca Meridian 36G with 13,000 miles on it. The passenger side side windshield just developed a horseshoe crack at the bottom. I set up an appointment to have it replaced at Barber RV in Ventura Ca. I asked the service rep what could have caused the windshield to crack as I couldn't find any indication it was hit by a rock. As he walked up and saw the location, he said that it was "rust". He then proceeded to pull away the rubber surround and the channel the windshield sits in was full of rust. I am curious if any other Winnebago/Itasca owners are having the same problem and if there is anything I can do to stop this from happening again? Thanks