windveilpete

Trying to figure this out. Put an american thunder flowmaster single on about two months ago. At first, it RATTLED now and then, so i tightened the hell out of the bolts.. no more rattle.

Two months later... i thought the bolts might be loose again, becuase at WOT at 2700 rpm or so, it makes this crazy high pitched vibration noise - not completely unlike but not at all the same as the old loose bolt sound...

It's kinda like a 2-stroke motorcycle sound even, just b-r-r-r-r-r-a-p! But REALLY tinny. TINNY! My wife even noticed it. Not good.

So, this started after I loaded the 93 octane tune too.

Think it is some sort of resonance problem brought on by the higher volume of flow by the new tune? Or a goofy muffler problem? (I guess I am gonna reflash to 91 tonight)

Any suggestions or ideas would be more than welcome! Thanks guys. Hope to see you at the 30th anniversary stampede this weekend!

Rrruss

Are you using the clamp that came with the Am Thunder? I found that I had to tighten it up a few days after installing it, was making weird rattling noises.

Had the same issue with it after I reinstalled it after removing it to take a 2400 mile trip thru Canada.

windveilpete

Hmm... well - I switched tunes on the way home to the 91 octane tune. Still does it, same place. I can get it to make the sound on acceleration, deceleration, and at a constant speed, no matter what gear. It's around 2750 rpm's, just much more pronounced at WOT. If I am sitting still, I can get it to make the sound with or without the car in neutral, clutch in, or out. For a second there, I thought it might be the clutch, but it's definitely coming out of the muffler when I stomp on it.

I will try the 15mm bolt on the clamp when it cools off, but don't really know what to think. It's pretty damned annoying though, i'm pretty close to just putting the stock muffler on there and saying "F" it

SPARTAN VI

I learned to live with the drone. I'll be dynamatting sometime soon anyway.

windveilpete

I have heard others speak of dynamat. What is it exactly... and how much does it cost? The rattles in my car are driving me APE$HIT - I can't believe a car that has been on the road for less than a year has this much vibration, interior rattles/noise and resonance issues. It's really beginning to affect my enjoyment here. Sad, really, when I first got this car, I was in LOVE with it. And I still love the way it looks, but MAN - did Ford just find the cheapest plastic they could find, and slap it in the car, or what? No wonder they are going bankrupt. I had a 10 year old acura (which had none of the great styling this car has) - but with 150k miles on it, it didn't rattle, squeak, and vibrate like this car does.

I think I am overdue for a visit with my dealer.

Thomas Ford

Solution: Flowmaster DUALS with H-PIPE!! You'll thank me. The H Pipe eliminates that ugly sound I used to have it too.
Tom

Puerto Rico 4.6

I have complained about the dash rattles to my dealer over and over again. They always comeback wih the usual " we cheked but coulnt find anything loose " [:@] My wifes ALtima has a year and a half and you cant even hear a peep even when going over the worst roads, but then again it was 5 grand more expensive than the stang.