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Posted

my 2014 chevy silverado will chirp every time it switches from v4 to v8.  I was reading that there may be a fix for this.  my truck has 40k miles on it and just out of warranty.  Will gm do anything for this since it is happening to thousands of trucks of all different years?

Posted

There is a tsb for it so they should. But I also have had the "fix" twice now. The new design doesn't chirp as much but it rattles loudly at idle. The old design you have has two square knobs. My advice would be to bolt it open and be done with it. The new design is not that easy to bolt the flapper open, but you would also be getting a new exhaust so that would be good I guess.

Sent from my Pixel 2 using Tapatalk

Posted

Pretty typical of the Exhaust Adaptive or "flapper valve"  just behind the muffler.

Mine use to chirp also during V4 to V8 and also on warm startups. Thought it was my starter.

Some here have reported GM replacing entire exhaust under warranty. 

Option 2 is to clamp the valve open or try to lubricate the heck out of it.

Posted

But if i clamp it open i have heard that it can do damage to engine.  Is this a true?

Posted

My flapper valve started chirping / squeaking during V4 / V8 transfer at 1500 miles..

Dealership replaced entire exhaust system with new style valve assembly..

Unfortunately, with 40K on truck,, chances are they will not replace,, by give it a try anyway,, nothing to lose...

As others have stated,, either lock it open or just remove..

May be time for exhaust upgrade to better / nice sounding system..

 

Cheers---K

  • 2 months later...
Posted

Just went today to my GMC dealership that sold me my 2015 Sierra last month for this chirping issue. They told me there is a new exhaust system for the 2015’s that will solve this flapper problem. Being under warranty still I will have it replaced within the next few weeks. I also told them there seems to be more vibration in the pedals while in motion than my 2004 model made. They told me the new suspensions are tighter and that there is more vibration felt in the newer models. So it seems newer isn’t always better in all aspects.

Posted

Had my 2015 looked at last week for the valve chirp but since I’m 6 months out of the 3/36 bumper to bumper warranty, they wouldn’t replace it no charge. It’s not covered under the 5 year power train warranty. I was quoted $800 for the new exhaust. Figured I’ll clamp it open or put the $800 towards a borla/Corsa exhaust. 

Posted

Clamp it open and save the cash.

Sounds better clamped open.

A little droning here and there but not real noticeable.

  • 1 year later...

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