Flowmaster American Thunder Cat Back rattle - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

mpgsux · 07-03-2011, 09:55 PM

Hey guys,

Just installed a Flowmaster American Thunder cat back on my 2010 SS today. First of all, the exhaust sounds awesome.

Here's my problem though. I have a noticeable rattle when I go over bumps. I know it has to be the tunnel brace. The manual said to have a 1/2" of clearance. I have know idea how to get that much clearance. The exhaust is almost sitting on the brace and I can't seem to get it to move at all. Any suggestions?

Also, I assume some white smoke it normal after installation. I drove to the gas station and back, about 2 miles total, and when I pulled into the garage there was a huge cloud of white smoke. I assume this is mainly due to stuff burning off the new exhaust, but it made me a little nervous at first.

Thanks guys!

Steve

RedRyder · 07-03-2011, 10:43 PM

I couldn't even put my tunnel brace back on after I installed mine haha I think your supposed to support the x pipe up with something and then tighten down all the clamps in order to have the proper clearance for the brace. Hopefully others who properly installed it will chime in.

And yes the white smoke is normal

thesnoopster · 07-04-2011, 12:28 AM

I have the same exhaust and I read and saw the video before installing mines and before you tighten up the exhaust, you have to jack up around the x pipe area while the bolts still loose and push it up far as you can, then tighten the bolts.

In addition, I brought another tunnel brace from elite for extra clearance.

I had my exhaust on for almost a year and no rattling noise.

Hope his helps

Camaro_hx · 07-04-2011, 12:53 AM

Faced the same problem, plus needs re-tightening after approx. 200km, as heat-expansion tends to loosen the bolts.

Unfortunately, altho its a great exhaust but the interior drone level was getting to me, so i ordered the CORSA catback and waiting for it to arrive and get it installed.

Anyhow, good-luck and im sure you'll enjoy it and will sound even better with time!

Meathead Camaro · 07-04-2011, 05:02 AM

I have the same problem, i installed the SLP loudmouth and it keeps hitting the tunnel brace.

I've had it on for 2 weeks now and want the rattling noise to go away, can i loosen the clamps and raise the H pipe from the brace then re-tighten the clamps? Or do i need an aftermarket brace?

thesnoopster · 07-04-2011, 10:44 AM

You should be fine if you loosen the bolt and push the exhaust up as high as you can get it and retighten the bolt. You can also get a brace for extra clearance as well (the one from elite works great).

RedRyder · 07-05-2011, 12:21 PM

Had some free time today so I loosened up all the clamps, jacked up the x pipe as high as it would go, readjusted/tightened the clamps back, and like magic the vibrations are gone

thesnoopster · 07-05-2011, 12:28 PM

Quote:

Originally Posted by RedRyder

Had some free time today so I loosened up all the clamps, jacked up the x pipe as high as it would go, readjusted/tightened the clamps back, and like magic the vibrations are gone

Good Deal!

07-03-2011, 09:55 PM	#1
mpgsux Drives: 2010 VR 2SS LS3 Join Date: Jun 2011 Location: Columbus, OH Posts: 11 View My Garage	Flowmaster American Thunder Cat Back rattle Hey guys, Just installed a Flowmaster American Thunder cat back on my 2010 SS today. First of all, the exhaust sounds awesome. Here's my problem though. I have a noticeable rattle when I go over bumps. I know it has to be the tunnel brace. The manual said to have a 1/2" of clearance. I have know idea how to get that much clearance. The exhaust is almost sitting on the brace and I can't seem to get it to move at all. Any suggestions? Also, I assume some white smoke it normal after installation. I drove to the gas station and back, about 2 miles total, and when I pulled into the garage there was a huge cloud of white smoke. I assume this is mainly due to stuff burning off the new exhaust, but it made me a little nervous at first. Thanks guys! Steve

07-04-2011, 12:28 AM	#3
thesnoopster Drives: '17 Fifty SS - '18 Traverse Redline Join Date: Jul 2009 Location: Northern Virginia Posts: 3,616	I have the same exhaust and I read and saw the video before installing mines and before you tighten up the exhaust, you have to jack up around the x pipe area while the bolts still loose and push it up far as you can, then tighten the bolts. In addition, I brought another tunnel brace from elite for extra clearance. I had my exhaust on for almost a year and no rattling noise. Hope his helps __________________ 2017 Camaro SS -"FIFTY" Mods: "93 Octane"

07-04-2011, 05:02 AM	#5
Meathead Camaro Drives: 2011 Camaro 2SS/RS Join Date: Jun 2011 Location: Chatham, NJ Posts: 113	I have the same problem, i installed the SLP loudmouth and it keeps hitting the tunnel brace. I've had it on for 2 weeks now and want the rattling noise to go away, can i loosen the clamps and raise the H pipe from the brace then re-tighten the clamps? Or do i need an aftermarket brace? __________________ TEAM L99 2011 Black 2SS/RS

07-04-2011, 10:44 AM	#6
thesnoopster Drives: '17 Fifty SS - '18 Traverse Redline Join Date: Jul 2009 Location: Northern Virginia Posts: 3,616	You should be fine if you loosen the bolt and push the exhaust up as high as you can get it and retighten the bolt. You can also get a brace for extra clearance as well (the one from elite works great). __________________ 2017 Camaro SS -"FIFTY" Mods: "93 Octane"

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07-03-2011, 10:43 PM	#2
RedRyder Drives: 2010 VR 2SS/RS M6 Camaro Join Date: Feb 2010 Location: Atlanta, GA Posts: 499 View My Garage	I couldn't even put my tunnel brace back on after I installed mine haha I think your supposed to support the x pipe up with something and then tighten down all the clamps in order to have the proper clearance for the brace. Hopefully others who properly installed it will chime in. And yes the white smoke is normal

07-04-2011, 12:53 AM	#4
Camaro_hx Account Suspended Drives: 2010 1LT/RS CGM Join Date: Sep 2009 Location: KWT Posts: 2,474 View My Garage	Faced the same problem, plus needs re-tightening after approx. 200km, as heat-expansion tends to loosen the bolts. Unfortunately, altho its a great exhaust but the interior drone level was getting to me, so i ordered the CORSA catback and waiting for it to arrive and get it installed. Anyhow, good-luck and im sure you'll enjoy it and will sound even better with time!

07-05-2011, 12:21 PM	#7
RedRyder Drives: 2010 VR 2SS/RS M6 Camaro Join Date: Feb 2010 Location: Atlanta, GA Posts: 499 View My Garage	Had some free time today so I loosened up all the clamps, jacked up the x pipe as high as it would go, readjusted/tightened the clamps back, and like magic the vibrations are gone