"I used the Foam Power product on my truck exhaust tip which always has mud and soot on it. A couple of sprays of Diesel Soot Foam, waited a couple of moments and then power washed it. Everything came right off with little or no brushing! It's amazing! I usually have to use the car wash scrub brush 3-4 times and rinse before it's even close to what Diesel soot Foam does easily! I use it on my entire truck with little to no spotting!"