I just installed the Aeroturbine muffler and PSD intermediate pipe from Diesel Power Products. I am very happy with the setup and sound. I keep the stock exhaust,and tail pipe. I replaced the muffler and added a PSD intermediate pipe, which goes from 3 1\2 to 4 " The setup is noticeable, The turbo spools up quicker the EGT temps are 100 degrees cooler. MPG are 21 mpg empty. Temps on EGT at 65 mph is 550 F . I do have a AFE air filter,with the air box drilled. I know some of you are wondering if the dreded droan is there on the sound. None to report. The sound at idle is deeper, and at acceleration the sound has some Bark to it. If you need some more info about this system contact www.dieselpowerproducts.com and ask for Dave.