The white wall tires on my Tbird had been liberally dosed with tire dressing by the previous owner resulting in them turning a yellow brown color. I tried all the usual things like soap pads, Westleys Bleche White, Simple Green and all the rest. Nothing worked and then I read online ( can't remember where ) about a guy the wet sanded his white walls with 400 grit sand paper.

Well today I loaded a rubber sanding block with some 400 ,used some warm water and Simple Green to keep the paper wet and went after the tires. The results were immediate and amazing, the white walls are white again. A good tip for those with nasty white walls or white letters.

Pete