Claybars do work. If you wash your car, and feel the surface with your finger (usually the hood, roof, trunk and bumpers) and you notice it is not smooth like glass, it's because "stuff" has stuck to or embedded itself to your paint (or clearcoat). Mostly the stuff is soot, carbon, tree sap, specs of tar, etc. The clay bar removes the impurities without damaging your paint. Get a good brand like Mothers or ClayMagic, some of the others leave streaks. You must use a lube spray while doing it (like a finishing detailer)-just rub back and forth several times (very manual procedure). I did it on my car and was amazed at how the surface became smooth like glass. The clay removes everything, including any wax. Polish it up and you have a nice looking brick!

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98 S70 - Forever stock