Make sure your clamp placement is like this (one leg of the clamp on either side of the alignment nub) and tighten them as tight as you can.
Attachment 2369Attachment 2370

Several of us TMSers have followed this pattern and have had trouble free exhaust systems.

 

I think THAT is my problem right there. My clamp is slightly before the alignment nut. Today when i fired it up before work, the right muffler was rattling again... and it really does sound awful until about 5 mins later when it warms up, then it disappears. I went out back and put my hand on the tip and the sound disappeared, so I'm almost sure its the clamp or a bolt to the chassis. When I get home tonight, im going to redo them both and push the clamps up some more, I'll keep you posted. THANKS!

 

Exactly what I was thinking when I crawled underneath there last night.
Lunch time Im going to pull in the shop and put up on lift and move the clamps to that position to see if it helps.

 

I'm just ribbing ya

Do you have a portfolio site up somewhere with more of your work?

 

Good point. Both of my clamps were right on top of that nub. My right muffler kept rattling and when I looked underneath, I saw that both were leaking. Un-did them, moved the brackets, and cranked them down. No more noise or leaks. Says alot for double checking your work...

 

Excellent!! the right one was making the noise, moved and retightend that clamp and all is good, for now.
So yeah Double check your work, and especially if you think you have the rattle in the Flows.

Thanks for the tip OKC, and chaulk another one up to the TMS!!

 

I love my flows. No problems so far (three months or so). You really don't notice the black muffler body under the body. Much less than the stock silver can actually. As for the tips, they are too large for my personal tast, but they DO fill the body openings very well. And they don't sound anything like a Fart Car, so I love them as is!

 

Redoing the clamp FIXED IT! However, I had to do it slightly different. I moved the front part of the ring past the muffler and onto the pipe, and the rear one was the one on the muffler. I did this so that it would slightly bend the tip and clutch onto the pipe like the one in your picture. The problem was the way it was clamped before, there was like a good 1-2mm space between the muffler and the pipe and it allowed for movement which made the rattling sound. Tightening the clamp just enough so that it held onto the pipe at the tip solidified that connection and now it sounds perfect. Thanks OKC

 

My Flows have been on the GT since last August. The blackout muffler color does it's job and focuses the eyes on the tips! I feel the Flows are the best sound for the money.

I had trouble with the install of the left muffler - it was too close to the top and the right side of the opening. I removed it and bent the rear mount arm inward about 3/8" which lowered the muffler and pulled it leftward just enough. I've had no trouble with rattles and don't remember exactly where I put the clamp - but those suckers were torqued down big-time!

I have an automatic car and do get a drone at about 1600-1800 rpm in 5th gear - with the stock airbox. Once I got my JLT CAI and installed the performance tune, the drone went away and was replaced by a mild growl at those rpm! And, of course, the Flows sound mean as hell at startup and when you are at WOT.

As was noted earlier, at highway speed (50 -90 mph / 2k-4k rpm) they are just purring. Long distance driving is very comfortable given the smooth mufflers and the road-noise compensation feature of the Shaker 500.

Chris