Over the years, I’ve seen just about everything used on rubber fenders. Back in the day, Pacific Coach (possibly a predecessor of Vision Coach) even painted them to match the chassis color, but that practice was likely abandoned because the rubber flexes while paint doesn’t hold up well under that stress.
I’ve noticed people using Armor All, tire dressings, and various other treatments. It seems we’re mostly stuck with the fenders as they are unless we opt for plastic ones painted in a preferred color.
Rick’s suggestion about the de-icing treatment for airplane boots is interesting. That stuff does protect rubber—my boots are 23 years old and still look great. I treat them with a UV-inhibiting product followed by ICEX to prevent ice from sticking. The combination gives a nice satin finish, but it’s definitely on the pricey side.
Personally, I find my car tires look just as good with simple, inexpensive tire dressing. As for my bus, I’ve come to terms with the fact that the fenders are a lost cause. I spent too much time trying to improve their appearance on my first coach, and the results just didn’t justify the effort. It felt like putting nail polish on a pig!
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