Review on Walker 21347 Quiet Flow Stainless Muffler by Michael Walker

I fitted this muffler to my 1998 Ford truck a while back. Immediately after installation, I achieved an increase in mileage and a decrease in fuel consumption and noise. The muffler was fitted direct from the OEM and installation was quick and easy. However, after a few years, the muffler began to corrode on the outside and formed several holes that rendered it unusable. This muffler is supposed to be stainless steel, but I tested it with a magnet and it has so much iron in it that the magnet stuck badly and was difficult to remove. I would guess that the material contains less than 7% Cr. At these low values I would not classify the muffler as 409 stainless steel or 309 etc. I bought another just to see if it was a production accident but the magnetic response was identical. look at my photos If you are looking for something that will last longer than OEM parts, I do not recommend this product. It is better to buy original OEM.