white07

Are you sure that all your bolts for the x-pipe to catbacks is still there? I had a rattle on my 96 with a mac o/r h-pipe and slp catbacks. Finally one day i looked to see what was making the noise and 2 of my screws on the same side fell out of the clamp.

Glen

Well, I had a very reputable shop work on my car (they specialize in fords, a ma-n'-pa business sort)....The first thing he said was "ALL the BBK X-pipes rattle like that."

He was right that there was no problem with the muffler, but the fact that it is so loud and I hadn't had this problem before makes me wonder before buying an entire new cat back.

Could it possibly be a header bolt or something?

snov001, is your F-150 modded with exhaust, or is the sound coming from elsewhere?? People who listen to it say they hear it coming from the front of the car, although I figured that maybe resonation was responsible for transferring the sound...

redass02gt

you probably have a leak. if it sounds like a spray can... and mostly when it's under load, but not getting much gas around 2000 rpm... that's what my leak sounded like.

on my bbk catted X, I had a leak on the driver's side manifold because the manifold stud had a flange on it which prevented the ball and socket joint from tightening up and sealing. I had a new stud put in, tightened it up, and no more rattle-can noises. if you've been driving around a few days, you should be able to look uinder the car near all the joints and find black soot at the leak.

Jonny.GT

I know it sounds really wierd but I had this issue when I did my first attempt to install my BBK X-pipe before it got too late.

My sway bar snapped and was bouncing around and I could have sworn it was comming from my exhaust...

I know its a long shot but just give it a looksie haha

QWK90GT

I know the sound your talking about mine did it all the time when I had my flowmasters with the bbk x-pipe. Now I have a magnapack catback and it crackles real bad at that rpm range.

Glen

Well, I found out what's causing the noise.

My buddy Joe at Autozone stuck his head down into the engine compartment while flicking the throttle, and a leak is very noticeable at the driver's side exhaust manifold...

Anybody have tips on how to tighten it up? He said it would be quite a job and a shop might have to take care of it....