[6605stang]

So this is a several years long saga. I got the FRPP mufflers a long time ago and they sounded fantastic. Then one they they developed a distinct rattle from the right side. Took it to a muffler shop and they told me a baffle had come loose. Kind figures... I bought them used on the forums. Couple days later I catch another good deal on a used set on the forums. Buy them, install them, SAME rattle on the right side?! I call FRPP and they say they did at one time have some issues with baffles letting go due to no drain holes in the original sets. Ok. So i'm buying new this time and making sure they have the drain holes... check and check. Get the new set on... STILL F'ING RATTLES! I've gone through the entire rear end area with a torque wrench and even over torqued some less important areas and I STILL CANNOT figure out where this rattle is coming from... Only thing I've been able to determine is if I put the stock exhaust on... it goes away.

Does anyone have any ideas here or have any of you experienced anything similar? I'm tearing my hair out over here.

 

[JBert]

Take the suspect muffler off, hold it in your hands, and shake it . . . if it rattles, they you know where the rattle is coming from. If there is a baffle loose inside, I doubt there is anything you can do except buy a new one.

 

[Blazin72]

I had an 07 that had an exhaust rattle that turned out to be a muffler hanger rubbing on the structure of the car. A sawzall and removal of about one inch of the hanger took care of it.

 

[6605stang]

Take the suspect muffler off, hold it in your hands, and shake it . . . if it rattles, they you know where the rattle is coming from. If there is a baffle loose inside, I doubt there is anything you can do except buy a new one.

Done that about 10 times. I put too much stock in the original diagnosis from the muffler shop. It's NOT the mufflers, unless i've gotten 3 bad sets in a row.

I had an 07 that had an exhaust rattle that turned out to be a muffler hanger rubbing on the structure of the car. A sawzall and removal of about one inch of the hanger took care of it.

Which hanger was it? I've heard something about this in the past, but every time I look it seems all my hangers are tight with clearance.

 

[shakin]

You need to make sure of exactly where that rattle is coming from. I've also heard of the cats getting too hot and having a bit of a melt down inside causing a rattle.
Can you replicate the rattle when the car is in a stationary position?
Does it happen at a certain rpm range?
3 sets sound like it's maybe something else. As asked before can you rattle the muffler when it was off the car? Is it a rattle or a vibration?
You're going to have to do some diagnostics to narrow it down, and once you've found it to figure out why it's occurring. Friends can really help you out for this. I can understand that this is frustrating.

 

[6605stang]

You need to make sure of exactly where that rattle is coming from.

I couldn't agree more.

I've also heard of the cats getting too hot and having a bit of a melt down inside causing a rattle.

Interesting, but the sound is definitely coming from the rear of the vehicle. I've had the wife drive around while I was pretty much in the trunk with my ear to the floor. Definitely coming from the area of the right muffler.

Can you replicate the rattle when the car is in a stationary position?

Nope.

Does it happen at a certain rpm range?

Nope.

3 sets sound like it's maybe something else.

Yep.

As asked before can you rattle the muffler when it was off the car?

Nope.

Is it a rattle or a vibration?

I would call it a rattle - a clanking/banging rattle of varying loudness.

You're going to have to do some diagnostics to narrow it down, and once you've found it to figure out why it's occurring. Friends can really help you out for this. I can understand that this is frustrating.

Agreed.

 

[Blazin72]

Which hanger was it? I've heard something about this in the past, but every time I look it seems all my hangers are tight with clearance.

I don't remember. It was one of the hanger rods welded to one of the mufflers.

 

[tbar]

There was this TSB.
http://cdn.lrsstatic.com/downloads/tsb05-14/tsb08-03-04.pdf

 

[ghunt]

Since you're saying it goes away when you put the stock mufflers back on, and it's NOT coming from the FRPP mufflers, that's telling me something is getting pushed/pulled out of whack when you install the FRPP mufflers.

If there's one thing I dislike about these cars it's that the only give you exhaust hangers at the transmission crossmember and at the mufflers with nothing in between.

I would say install the FRPP mufflers and check EVERYWHERE that something could be touching something else. Hangers, pipes, etc.

 

[northern c/s]

just reading through this and it sounds smiilar to what I went through. If you take the palm of your hand and hit it against the exhaust tip hard, can you replicate the rattle? I found in mine i could and te problem turned out to be an interference as the exhaust moved. i had to adjust the pipe to muffler fitment by just over 1/4 inch shorter and problem was gone. Good luck