ANYONE HAD EXHAUST FLAPPER VALVE REPLACED?????

tbare54 · October 4, 2014

Anyone had there exhaust flapper valve replaced by the dealership???? My 4.3 DOUBLE CAB was in the shop for recall and dealership called me and said it had a defective flapper valve and they were going to order parts for it. They called today and said the repair involved a complete exhaust system and the exhaust system came in, but they didn't get it completely installed.

Is this what other people have had done to there trucks, for the problem??????

newdude · October 4, 2014

There is a service info piece in GM that if there is an issue with the valve, to put a bolt in the mechanism and keep it open. If any noise goes away, replace the exhaust system.

glcbn · October 4, 2014

Anyone had there exhaust flapper valve replaced by the dealership???? My 4.3 DOUBLE CAB was in the shop for recall and dealership called me and said it had a defective flapper valve and they were going to order parts for it. They called today and said the repair involved a complete exhaust system and the exhaust system came in, but they didn't get it completely installed.

Is this what other people have had done to there trucks, for the problem??????

There is a service bulletin for exactly what they are doing to your truck. So yes, it is the procedure.

There's a thread somewhere about this, but I can't find it.

Silverado-Hareek · October 7, 2014

I'm saving my money to cut everything out from the muffler back and run a new pipe without the flapper valve or the resonater. I miss that throaty sound of a stock GM truck exhaust and I'm pretty sure I can feel back pressure from the exhaust system in the gas pedal when it switches to V4 mode. They claim these new trucks were designed to mask the switching between V8 and V4 better than the GMT900's but I can feel it all the time in this truck and I never felt it at all in my 2007. Weird.....

14SLTZ71 · October 7, 2014

There is a service bulletin for exactly what they are doing to your truck. So yes, it is the procedure.

There's a thread somewhere about this, but I can't find it.

http://sandyblogs.com/techlink/?p=3296

glcbn · October 7, 2014

http://sandyblogs.com/techlink/?p=3296

Thanks for posting that link.

14SLTZ71 · October 7, 2014

Thanks for posting that link.

You're welcome

TJay74 · October 9, 2014

yep, entire system to fix it. it is all welded together so no way to get the flapper valve out. I had my muffler changed out, flapper cut out along with the resonator and love the sound.

MoebiusFX · October 14, 2014

I brought my truck into dealer yesterday for squeaky flapper valve, and they also ordered parts to replace exhaust under warranty. Out of curiosity, anyone know what's different on the replacement? Do they remove valve entirely or provide a different type? I'm not sure what to expect, but would hope it's not just the same thing with the same issues.

MoebiusFX · October 21, 2014

FYI for those with this issue, GM did replace the exhaust system under warranty. The new exhaust still has a flapper valve, so I'm curious to see how this one holds up, hoping it will not start squeaking in a couple thousand miles like the first one. In any event, the service bulletin listed on my invoice is PI 1199A.

MoebiusFX · November 12, 2014

An update on my experience... After my exhaust was replaced under warranty to address the squeaky flapper valve, I noticed increase vibration in the gas pedal/floor. The dealer realigned where the exhaust is attached, and that seems to have helped with the vibration some, so that's good. The noise from the valve was gone for nearly 3 weeks - however, I've now started hearing it again. So it appears the replaced exhaust system, which still includes the valve, doesn't prevent the issue from reoccurring.

Interesting note on the timing of the return of the squeak... It was fine until driving this past weekend in heavy rain/snow/winter-mix conditions. I'm wondering if the squeak comes more quickly for folks that drive in wet/wintry conditions that would cause any lubricant the factory might have put on that valve to wear off faster.

Does anyone know if there's simply a way to lubricate the valve to prevent/minimize the squeak, or the best type of lubricant/grease to use since I imagine this area both gets very hot, and is often subject to moisture in rain/snow.

stevev · November 12, 2014

A person in another post recommended to apply some hi-temp anti-sieze compound to the exhaust valve spring. You just brush it on.

http://www.grainger.com/product/LOCTITE-Anti-Seize-Compound-3KE65

disappointment · November 14, 2014

Bought a 2014 Sierra dbl cab, 4.3 echotech motor, work package last February. Right out of the box I noticed a vibration at cruising speeds ( 50 mph or less ) and have had it back to the dealer 6 times to correct the issue. The culprit, they say, is the flapper valve behind the muffler. Holding the gas pedal absolutely steady when the motor is idling along on 4 cylinders at a steady speed and then needs an increase in power, which means shifting down, the whole drive chain starts to shake right back through the steering wheel. Felt like a broken motor mount or bad plug wire. After putting a complete new exhaust on most of the problem was corrected but is now slowly coming back, exactly as it happened before. Wonder what all that back compression because of the flapper not working correctly is doing to the valves and other components of the engine. Not to mention what the vibration is starting to shake loose.I have to constantly keep moving the accelerator to make the shaking stop, so either I am right on someone's bumper or I am holding up the flow of traffic.

I have been told to just drive it and see how much worse it gets. For $32,000 is this an acceptable response? Mine cannot be the only one to be doing this as the dealership has led me to believe. They also told me there is a certain amount of acceptable vibration associated with the shifting of the transmission.

Anyone else had this problem?

sthom2255 · November 15, 2014

I just bought a 2014 sierra 1500 reg cab/reg bed.

less than 500 miles and I am getting that sound.

the GMC dealer told me the same thing. they have a new exhaust system on order.

the noise sounds like a defective u joint !!! I get the noise on acceleration and deceleration.

I only get the noise after the englne temp. comes up to normal.

it makes sense it would be the flap or baffle in the muffler, but, I don't get the sound

after the engine and exhaust system heats up and I am sitting in a parking lot..... pressing on the gas pedal.

the new system is going in this coming week.

will see If they are correct!!

LtSteve · November 18, 2014

I too have had the exhaust on my 15 Tahoe replaced once due to squeaky flapper valve in exhaust. After about 2 months, the squeak has returned. Tried to get dealership to again do something about it, but they were stop in their tracks by GM Technical Assistance who stated, "This is an inherent characteristic of the exhaust system." Therefore, I filed a complaint with GM Customer Service and they are not willing to do anything else. REALLY?! This is my 3rd Tahoe and have never had a problem like this. I am getting so angry that I am ready to trade in my 15 Tahoe, take the hit on depreciation, and by a Dodge Durango. What gives?