When im in park and at real low idle my exhaust pipes and mufflers vibrate like no other all over the place but when im driving the car at a regular speed and rpm it completely diminishes.

I am told that its a "Harmonic Noise" coming from the engine that is making the exhaust do this. Does anyone have an idea ofwhat i should doto remedy this? Greatly appreciated, Thanks

 

I think the vibrationmay be caused by the hangers near the CAT touch the brackets when you installed the dual exhausts.. ( The brackets are at the crossmember).

 

There is a TSB for this:

http://www.2005stang.com/gallery/alb...%20console.pdf

 

Well i had them recheck the exhaust work, then i took it to the ford dealer and had them check it out. The place that did the exhaust said its all correct and its not the exhaust. Well the ford dealership said its because i have no H or X pipe so the mufflers and both pipes are vibrating bad until i get going then they placed a bar in between the pipes like an H and it stopped vibrating. But when i took it back to the shop where the work was done they told me when they placed a pipe in there that the vibrating worsened and they didnt think putting the h pipe in there would remedy it. Therefore they called it a harmonic engine noise yet ford found nothing work with the engine. I honestly dont know what to do...

 

I was having the same problem with my car with the duals, in that same RPM range it sounded like the exhaust was going to rattle off the car. I took it back to the muffler shop I watched they pound the exhaust but they could not find anything either, I took the tech on a ride in the car and I could not re-create the sound. I am aware of the trials of putting duals on a V-6 so I guess I will have to see if I can re-create the problem