When installing one of these systems the first thing you do is cut the stock exhaust pipe in front of the muffler. The STS Turbo System takes the place of a stock muffler and gives the truck a throaty aftermarket sound. You can see the weld where the STS pipe mates right up to the stock pipe. Installer Mark Eggers says that you can band clamp the two pipes together, if you don't have a welder, although he says welding is better. Of course, removing the muffler means you'll have to fabricate a new tailpipe but that's a small bit of labor for the gains you get.