A couple of weeks ago, I started hearing an annoying rattle coming from my passenger side Flowmaster A/T exhaust. The rattle/noise was apparent when starting up the car and while ramping the accelerator. A local muffler shop inspected the installation and determined that nothing was loose externally. They commented that an internal baffle may have came loose.

Has anyone heard of such a thing occuring? If so, is the only remedy buying a new exhaust for this side?

Currently, I cannot hear the rattle on start-up; however, there is a noticeable reduction in sound (throatiness).

Thank you
21MSU
2005 Mustang GT (Redfire)
Flowmaster American Thunder Exhaust
Boyd Coddington Junk Yard Dogs (18X9; 18X10)

 

Yes ,this is a known problem with the Flowmaster A/T Axlebacks. Flowmaster knows about it and all you have to do is call them, tell them your problem, and from there they ship you out a new set as long as you have a purchase recipt i think.

 

Yep, known issue. Mine started at 14 months old. Drivers side, at 2100 RPM. They were still covered under the warranty.....

 

same issue here... 1 yr after install, I began to hear a buzz/rattle.. turned out to be an internal broken baffle weld. Flowmaster immediately sent a replacement set. I also noticed it after shutting car off and closing door, the vibration of closing the door was enough to make it rattle. All is good now with the new set.

 

Yeah it's a known issues but pretty rare on any manufactured in the last year or so. As mentioned above they swap it out nice and quick for you.

 

 

Mine did it too. Flowmaster customer service was A+. They sent me a new set asap. The new ones have a reinforced baffle in them.

 

I wonder if that is what I am hearing. I have flowmaster 40 series, and I hear a rattle on the passanger side. The rattle is most noticable at hwy speeds. I don't notice it at idle.

 

Bumping up an old thread...

Several months ago when driving (very slowly) on a dirt/gravel road in the Smokey's I scraped something underneath my car while going over a bump. Ever since then, I have a minor rattle at 2600-2900 RPM's. I always assumed I knocked a exhaust clamp or something loose. Over the weekend while changing my oil, I hunted around every part of the exhaust and tightened up all connections. I tapped all the pipes with a hammer and couldn't find the rattle. The rattle is still there so now I'm thinking I have the dreaded 'Flowmaster Internal Rattle'. Will they still warranty these since my receipt is long gone?

 

From my personal experience, no. I removed my Flowmasters and placed them in the trash where they belong. It's a shame because they really do sound awesome.

 

I've had mine 2yrs+ with no issues. Guess I am lucky. Knock on wood.

 

you mean the set you sold me without mentioning that they were a replacement set?

Be careful in what you are representing as fine...

 

Mine are going back soon. Just waiting for my pypes mid muffler to show up.

 

Mine were fine, too, if I had not scraped them they might have been noise free forever.

 

That is why I will never buy a Flowmaster product ever.

That is so bad.

 

Ouch! Pwned!!!

I have had good luck with my Flows... installed Nov 2005, and still going strong! The only evidence that they are nearly 3 years old is the discoloration at the base of the chrome tips...

I'd say they are a solid product and a good purchase. I'm happy with them now as I was three years ago.

 

LOL. That is ridiculous. I'm glad I sold my Flows after 2 months.

 

A product called Never Dull from Eagle One will bring those tips back to like new. Available at any autoparts store.

 

I tell ya what tho, they sent me a new set at no charge and no hassle after 2 years old. Good customer service is sometimes hard to find. I believe the written warranty is only 1 year also.
Above and beyond Flowmaster went for me.

Note* The replacement set went up for sale