Ok, I have a 2000 7.3l psd with 81,000 miles. I recently changed the oil,oil filter, fuel filter, and installed a diy intake. While on my way home from work today, I put my foot in it and noticed it blowing thick black smoke. It's never blown any smoke at all. I was pretty impressed when I saw it, but then I quickly started wondering if it was normal (since it has never blown smoke ever and is pretty stock)?? It could have blown smoke in the past and I just never noticed it, but for whatever reason it got my attention today.