For the section that is having the problem, consider keeping that section of the coach heavily waxed. I do mean frequent (like weekly) waxing, so the sun hits, disperses the heat and wears away the wax first. There is no guarantee this will work, but the owners I talk to say it dose seem to slow the spreading down quite a bit.
2005 Newmar KSDP 3910 + GMC ENVOY XUV 37K lbs Moving Down The Road
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