I have 2 chamber flowmasters w/ an off road H-pipe. In the last day or two, I have developed what sounds like metal on metal buzzing sound and its loud.

It only happens when the throttle is applied lightly and within a very small RPM range. (Example: cruising down the street at 30 mph and giving enough throttle to keep that speed)

I crawled up underneath lastnight and wiggled, knocked and banged on everything. It all seems to be tight.

Is this what a broken flowmaster sounds like??[sm=smiley22.gif]

 

Yup. Sure sounds like it. I wish I could post links to "the other board" over here. dustindu4 has a couple of threads on the subject. He is on either his third or his fourth set of American Thunder Flowmasters for that very reason.

 

Can you tell me when you bought them? Your supposed to hear a rattling if you tap on them in the back with a rubber mallet. The reason I'm asking when you bought them is they had problems at first. Did a fix, still had problems now Flowmaster says they got to the root of the problem on the third fix. They told me if you bought them in the last few months you should not have any problems. They should replace them but you will probaley need the invoice.

 

Are you sure it's not something inside the car vibrating? My FRPP's cause a vibration at a certain rpm that sounds like it's coming from the roof, it's hard to tell.

 

I bought them back in feburary. Ill try tapping on the back of em, thanks.

One way or another, the noise is an exhaust issue. It buzzes from underneath the left side of the car. Ill crawl back up underneath of it sometime this week...

 

Sounds like a busted baffle. Make sure to go to Flowmaster directly for the replacement.

 

interesting, I am just now getting a buzz in a narrow rpm range (on one side of car) with my "magnadrones".

anyone heard of similar thing happening with magnaflows?

 

Same thing with the magnaflows... going under 30MPH, small RPM range, partial throttle, and I get this vibration directly below the driver's seat. I wonder if an H/X pipe will fix this.

 

Most of my problem is that I have an off road H pipe. That set up produces alot of noise/harmonics that shakes things around. Getting a new x or H pipe may not solve the issue with yours.

I havent figured out whats causing my buzzing yet either. If I get incredibly bored over the weekend, Ill swap the flowmasters out with the stock muffs. Ill keep you all posted.

 

same thing happened to me a while back on my silverado with flows, there was a buzzing noise between a range that was only a few hundred rpm. turns out the baffling somehow came loose.