Noise after headers install

ajmalian · October 22, 2016

Hey guys,

Need some help. I've got a 2016 Sierra Denali with a cold air intake,Whipple supercharger, Gibson short tube headers alongside with an aftermarket cat-back exhaust.

I know I'm probably going to get roasted for the shorty headers but unfortunately long tubes are illegal where I'm from and to be very honest, I have heard long tubes with the after market cat-backs on the GM 6.2L....WAYYY TOOOO LOUD!!

Coming to my issue, where I need your expertise is that there seems to be this noise from the driver's side footwell after I installed the short headers. Can't even describe whether the noise can be calleded a clicking/ticking/chattering or what, I have absolutely no idea. All I know is that it comes with acceleration. If it was a constant I wouldn't mind but it's super annoying because it's got a mind of its own. Sometimes it's not even there, then it decides to come back and even when it does, it doesn't always present itself at the same volume. Sometimes its at a soft volume, then sometimes medium and sometimes quite loud, however all the times it is with the acceleration. Most of the time it's there, it's there at a medium volume.

At first I had my dealership install JBA short headers. We got this sound and my dealership claimed it was a leak. They resurfaced/machined the headers down, TWICE, changed the gasket even once, yet the sound remained. Then we changed over to Gibson short tube headers and unfortunately the same issue here too....

At the end they just gave me my truck back and said this is how short headers are and nothing can be done about it. Apparently they claim they spoke to JBA and Gibson and it seems they were told by them that it is due to the difference in size of the exhaust outlet in the engine and the inlet on the headers. I somehow don't believe my dealership because they always try to pull a fast one when they can't solve a problem.

I've attached an audio file, please tell me what you think the problem could be.

The dealership had my car for 43 days and after all of the fiasco above, they said whatever it is, it certainly is not a leak...

so...PLEASE HELP!!!!!

Voice 001_sd.mp3

jrodriguez_20807 · October 22, 2016

Sounds like a header leak to me..

cbrsilv15 · October 22, 2016

I had JBA shorties on my 07 and they sounded just like that. There was a leak somewhere. I couldn't find it. My truck now will stay without headers so I don't have that prob again. It def sounds like a leak somewhere, it just sucks the Gibson ones do too.

ajmalian · October 22, 2016

There has got to be a solution to this because the sound drives me crazy. Anyways, thanks for the feedback. I will still keep checking in for more info if any.

15_silverado · October 22, 2016

Google and try to find Percy's High Performance exhaust gaskets for your engine. I'm not sure if they make them for these new ecotec engines or not but if they do they are the absolute best. They are thick and crush when installing, and will seal even the most of leaks. I read they machined your headers twice but if the head on the engine itself is slightly out that won't help. If it is a leak do to gaskets these will definitely fix it. These have saved me before on a mustang cobra one time,I had the same horrible noise on the first start up and it was so bad it scared meat first but Percy gaskets fix my leak, they are well worth the money. Also check for leaks at the bottom of the header at the collector and where that gasket flange meets the piping. Google Percy's High Performance exhaust gaskets. Good luck. Let us know.

muddkatt · October 24, 2016

they said whatever it is, it certainly is not a leak...

Voice 001_sd.mp3

They are wrong, it IS a leak. My 2001 that has a couple of broken manifold bolts sounds exactly the same way.

chrislcrews · October 27, 2016

Hey guys,

Need some help. I've got a 2016 Sierra Denali with a cold air intake,Whipple supercharger, Gibson short tube headers alongside with an aftermarket cat-back exhaust.

I know I'm probably going to get roasted for the shorty headers but unfortunately long tubes are illegal where I'm from and to be very honest, I have heard long tubes with the after market cat-backs on the GM 6.2L....WAYYY TOOOO LOUD!!

Coming to my issue, where I need your expertise is that there seems to be this noise from the driver's side footwell after I installed the short headers. Can't even describe whether the noise can be calleded a clicking/ticking/chattering or what, I have absolutely no idea. All I know is that it comes with acceleration. If it was a constant I wouldn't mind but it's super annoying because it's got a mind of its own. Sometimes it's not even there, then it decides to come back and even when it does, it doesn't always present itself at the same volume. Sometimes its at a soft volume, then sometimes medium and sometimes quite loud, however all the times it is with the acceleration. Most of the time it's there, it's there at a medium volume.

At first I had my dealership install JBA short headers. We got this sound and my dealership claimed it was a leak. They resurfaced/machined the headers down, TWICE, changed the gasket even once, yet the sound remained. Then we changed over to Gibson short tube headers and unfortunately the same issue here too....

At the end they just gave me my truck back and said this is how short headers are and nothing can be done about it. Apparently they claim they spoke to JBA and Gibson and it seems they were told by them that it is due to the difference in size of the exhaust outlet in the engine and the inlet on the headers. I somehow don't believe my dealership because they always try to pull a fast one when they can't solve a problem.

I've attached an audio file, please tell me what you think the problem could be.

The dealership had my car for 43 days and after all of the fiasco above, they said whatever it is, it certainly is not a leak...

so...PLEASE HELP!!!!!

Voice 001_sd.mp3

Kinda off topic but. Do you have your truck lifted with the supercharger? Looking at them they are 6k. What benifiets do you have? Besides increased. Hp? Can't find any video on them so figured I would talk to someone who has one for our trucks!

ajmalian · October 27, 2016

Kinda off topic but. Do you have your truck lifted with the supercharger? Looking at them they are 6k. What benifiets do you have? Besides increased. Hp? Can't find any video on them so figured I would talk to someone who has one for our trucks!

First off, no my truck is not lifted. Secondly, what are you referring to with 6k, the price? As for benefits, yes it was to squeeze each and every possible HP out. Truck is yet to be tuned so got my fingers crossed. Gotta wait and see what really would be the benefit.

chrislcrews · October 27, 2016

First off, no my truck is not lifted. Secondly, what are you referring to with 6k, the price? As for benefits, yes it was to squeeze each and every possible HP out. Truck is yet to be tuned so got my fingers crossed. Gotta wait and see what really would be the benefit.

Yes price for the supercharger. Mine is lifted I thought about putting a supercharger on it but dunno if I really will or need too.

I was reading on their website. The whipple has a 4 gallon water tank on it?

Sent from my iPhone using Tapatalk

wuznme · October 27, 2016

Yes price for the supercharger. Mine is lifted I thought about putting a supercharger on it but dunno if I really will or need too.

I was reading on their website. The whipple has a 4 gallon water tank on it?

Sent from my iPhone using Tapatalk

Not sure where you read 4, but it is barely the 2.5 as stated on the Whipple website.

PS Can never have too much power!

PSS Never too much power!

Kbuell21 · February 22, 2017

Did you ever figure out what the sound was? I'm having same problem with my headers.

GRN69CHV · February 22, 2017

I'll second the Percy's dead soft aluminum gaskets. Multi layer design. Absolute, hands down best.

thewhitestallion · February 23, 2017

100% exhaust leak (aka header leak)....

get a spray bottle and put a little soap in it. spray around the manifolds and don't forget to check where the collector connects to your y-pipe. The water and soap will begin to bubble up if exhaust is coming out where it is not suppose to be.

Hoginedgewood · February 23, 2017

100% exhaust leak (aka header leak)....

get a spray bottle and put a little soap in it. spray around the manifolds and don't forget to check where the collector connects to your y-pipe. The water and soap will begin to bubble up if exhaust is coming out where it is not suppose to be.

i was going to say, drape a long strip of toilet paper slowly around till there's a breeze, or wave a incense stick, but bubbles sound like a good test also.

Eddie 70 · February 23, 2017

I have header leaks before. While Percy's may have worked for some they didn't for me. The bolts kept backing out and I would have a leak again after a short trip. I could retighten the bolts and next test drive, exhaust leak. I finally broke down and bought a set of Stage 8 locking fasteners. I have not touched the bolts since installing them and have had zero leaks. This is in the car in my avatar with an LS motor.