Hey guys new user here. Here is my problem i have a 2008 Big Horn 5.7 quad cab with the 40 series flowmaster muffler. I have a constant squeling sound it does not go up or down with rpm levels it is just constant. I have had my truck checked out its not fuel pump bc the dealer replaced it didnt help the sound. It is not transmission two mechanics agreed on that at two dif locations. Now this noise did not occure until i hit a fully auto carwash as soon as the bottom pressure hit it started making the noise. I thought it was belt it is not everything is fine motor wise and transmission wise and fuel pump wise everything is fine up front. Now i have been told it is exhaust related bc the dealer scoped it and he hears this noise in the exhaust tube. So what do you gentlemen think of this situation? What am i missing i am getting very irritated at this noise bout to replace whole exhaust for this noise. Sounds like a constant chirp all the time.