Hello, I'm new here so please excuse my newbie questions, but can someone tell me how loud the turbo is supose to sound inside the vehicle with the windows rolled up? The reason I ask is because when I first got my truck ( a used 1995 5. 9 liter ram 3500) The turbo noise was quite loud kinda like the noise you hear in a jet though not as loud. Now I can barley hear it. Which is normal?