I think that "lettering" is plastic instead of metal.
__________________ 2000 Winnebago Ultimate Freedom USQ40JD, ISC 8.3 Cummins 350, Spartan MM Chassis. USA 1SG, retired;PPA,Good Sam Life member,FMCA. "We the people are the rightful masters of both the Congress and the Courts - not to overthrow the Constitution but to overthrow men who pervert the Constitution." Abraham Lincoln
Yes, it’s plastic letters with metalized “chrome” film over the letters. Not sure what could cause that nor what could clean it. Be careful it’s not super durable. In fact, that staining could be the “chrome” failing on the film and you are seeing the plastic under the film showing through the film.
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2017 Winnebago Adventurer 37F
2016 Lincoln MKX Toad
Yes, it’s plastic letters with metalized “chrome” film over the letters. Not sure what could cause that nor what could clean it. Be careful it’s not super durable. In fact, that staining could be the “chrome” failing on the film and you are seeing the plastic under the film showing through the film.
I think this is correct. Water gets underneath from behind—like mirrors in a home that evidence that.