2000 Adventurer 37U, great coach so far. New to us last Sept. Right after we brought it home, the Decal above the Windshield, (the one that says Winnebago) started to develop what looks like a rust colored stain on it. Rust color only, no obvious rough coating. I have tried several different cleaning products including BarKeepers Friend but nothing seems to clean any of the stuff off.

In fact, it does seem to be making it worse. As a last resort I may have to just remove the Decal.

Has anyone else had this problem? It also appears that what looks like a clear coat is beginning to come off.
When we brought the Coach home it only had 24000mi on the Odometer and from the looks of the underside I would say that the mileage is correct.