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Posted

Thanks FD. I really need to get a better understanding of what the booming vs the buffering is.

 

I hear the low boom at low speeds when I hit bumps or on rough roads.

 

And the sound at 41 and 71 sound the same just louder.

 

I dropped the truck off for its third Rob today on the Bridgestones. If this doesn't work, the next step will be havong them replace my tires with the Michelin Defenders.

 

I had them give me a copy of the TSB for the exhaust booming while I was there since it's been updated to include the 2016s.

 

I guess I'm going to have it tackle this one thing at a time.

 

For months, I thought the 40mph/70mph and the low speed boom were one and the same. They could very well be, but their inputs are different.

 

What you call "low boom at low speeds" is what I called "the boom" which was fixed with those exhaust dampers. The 40mph/70mph is similar. More frequent, but less intense. Equally as annoying!

 

You should be able to fix the 40mph/70mph buffeting more easily because GM seems to acknowledge that 15lbs RFB is their threshold for our trucks. They may have even documented this somewhere. It's just a matter of having their techs spend some time with your tires, remounting/rotating and replacing as necessary till they get it. It took 6 Continental replacements and 2 KO2 replacements to get mine right. Before buying/replacing, have them agree to deliver all 4 with under 15lbs of RF ahead of time because of this unusual requirement. I'll also note that I could hear the buffeting with rear wheel RF of 18lbs. All of mine are 12lbs or better and the buffeting is gone.

 

I recall reading earlier in this thread that GM was to update the exhaust this summer to address "the boom". Not sure what came of that, but admit that I haven't been following as closely since my issues were resolved.

 

Good luck and keep at it as it's an awesome truck once the bugs are worked out. This is the price we pay for buying early in a new model!

Posted

 

For months, I thought the 40mph/70mph and the low speed boom were one and the same. They could very well be, but their inputs are different.

 

What you call "low boom at low speeds" is what I called "the boom" which was fixed with those exhaust dampers. The 40mph/70mph is similar. More frequent, but less intense. Equally as annoying!

 

You should be able to fix the 40mph/70mph buffeting more easily because GM seems to acknowledge that 15lbs RFB is their threshold for our trucks. They may have even documented this somewhere. It's just a matter of having their techs spend some time with your tires, remounting/rotating and replacing as necessary till they get it. It took 6 Continental replacements and 2 KO2 replacements to get mine right. Before buying/replacing, have them agree to deliver all 4 with under 15lbs of RF ahead of time because of this unusual requirement. I'll also note that I could hear the buffeting with rear wheel RF of 18lbs. All of mine are 12lbs or better and the buffeting is gone.

 

I recall reading earlier in this thread that GM was to update the exhaust this summer to address "the boom". Not sure what came of that, but admit that I haven't been following as closely since my issues were resolved.

 

Good luck and keep at it as it's an awesome truck once the bugs are worked out. This is the price we pay for buying early in a new model!

So bad news.. The dealership couldn't properly assessment my vibration and booming.

 

They are putting me in a long term rental while they bring GM out to address the issue. There's also another 2016 that came in yesterday with the same issue.

 

This royally sucks. Two week old truck with 1000 miles.

Posted

I had them give me a copy of the TSB for the exhaust booming while I was there since it's been updated to include the 2016s.

 

 

What is this TSB for booming of which you speak? Haven't heard about that. Any chance you can take a pic of it and post it? My 2016 Yukon Denali has no issues other than booming and an extremely stiff ride. The ride I can deal with; the booming, not so much.

  • Like 1
Posted

 

What is this TSB for booming of which you speak? Haven't heard about that. Any chance you can take a pic of it and post it? My 2016 Yukon Denali has no issues other than booming and an extremely stiff ride. The ride I can deal with; the booming, not so much.

Yes. I'll take pics and post them this evening.

 

It's PIT5404A. It was recently just updated to include 2016 with booming.

 

It basically states that if there is booming and pressure in the cabin that is still present with AFM off, that it's being caused by vibrations.

 

There is a series of trouble shooting steps using RFB, picoscoping, exhaust replacement, or Active Noise cancellation that needs to be done.

 

The roof sheet metal TSB, does not apply to the 2016. It states the roof attachment was corrected as of July 2016 which targeted the buffeting.

 

This TSB targets the booming which they believe is being caused by the noise cancellation or the exhaust. And the vehicle vibrating excites it.

 

Here it is for the 2015.

 

http://gm.oemdtc.com/6100/buffeting-vibration-drone-type-noise-exhaust-tone-change-body-pressure-booming-afm-exhaust-2015-cadillac-chevrolet-gmc

 

This TSB has been revised to include all 2016s.

  • 2 weeks later...
Posted

Been a lurker for a while following the forum. Have a 2015 Tahoe LTZ. The buffeting and booming had gotten to where the vehicle was very hard to drive. You would have ringing in your ears after a short drive. Our dealer Beaty Chevrolet has been great to work with. They put an updated exhaust system on ours and it made a huge difference in the booming and buffeting. It's still there but I would say they took 80-85% of it out with the new exhaust. We've had lots of things tried like ring and pinion, tires etc. but nothing made a difference until this. Thought I would share.

Posted

Thanks for the update, Jim. I asked a while ago if anyone found relief with the "exhaust fix" on this forum. Do you know what the updated exhaust consists of and do you know by any chance if the 2017's have the "updated" exhaust? I am sure others would be interested on with any details regarding this fix. I may try for a third time with a 2017, but need some confidence they have at least addressed the exhaust with the new ones. Thanks again for your post!

Posted

I'm not sure on what it consists of. From what it looks like underneath it looks like from the muffler back is all new. We're on 2 weeks now with the new setup and I keep waiting to here the booming but don't anymore. Time will tell I guess. There is still some buffeting but it's very little. I'm not sure whether the new ones have this now or not. I would assume they do.

Posted

I'm gonna keep working with my dealer on getting the remaining buffeting out. It's not bad at all now but for the 70k we paid for this it's not gonna make a sound.

Posted (edited)

Been a lurker for a while following the forum. Have a 2015 Tahoe LTZ. The buffeting and booming had gotten to where the vehicle was very hard to drive. You would have ringing in your ears after a short drive. Our dealer Beaty Chevrolet has been great to work with. They put an updated exhaust system on ours and it made a huge difference in the booming and buffeting. It's still there but I would say they took 80-85% of it out with the new exhaust. We've had lots of things tried like ring and pinion, tires etc. but nothing made a difference until this. Thought I would share.

Hi Jim-

Do you happen to know the TSB # for the exhaust replacement? I was told back in July of 2015 that the exhaust TSB would be released in October, that is October of 2015. Fast forward almost a year later with me checking every 2 months with the dealership to see if the Exhaust TSB has been released (to no avail) and this is the first mention of anyone actually having the work completed.

 

Many thanks.

Edited by cleanfreak
Posted

I'm not sure on what it consists of. From what it looks like underneath it looks like from the muffler back is all new. We're on 2 weeks now with the new setup and I keep waiting to here the booming but don't anymore. Time will tell I guess. There is still some buffeting but it's very little. I'm not sure whether the new ones have this now or not. I would assume they do.

 

 

Any information you can provide on this would be appreciated. Even the name of your dealer would be helpful. I think there are a lot of people that have been waiting on this.

Posted

I hate to not have specifics but I dont. Even on my service ticket it doesnt say what they did. I was just told by the service manager what they did. I took it in for the booming and buffeting. The service manager and I know each other real well by now. They have had it on several different occasions for other issues Ive had with it. This thing has been a gremlin for noises. This specific time I took it in for the booming/buffeting. Other times have been rearend whine, whistling noises, vibrations. The booming/buffeting has always been there but it was very faint and kind of last on my list to address. After a recent oil change/ tire rotation it got very bad. They had it for a week and kept updating me daily that they were still trying to find the source. Near the end of the week they called and told me they had an updated muffler they took off another vehicle and tried it on mine and they were kind of floored by the difference it made. They told me they were going to order the updated one for mine and it had to come from GM and it might take a couple weeks to get. Then the next day they said GM told them to leave it on mine and they would order the replacement for the other vehicle. When I picked it up I asked if they took it off a new one on the lot and he said no it was ordered for another customers vehicle who has having the same issues as mine. Maybe a picture would be worth a thousand words. Ill try to take some and post them so we can compare. Ill try to get more answers from the dealer as well. After a couple weeks of driving it I can definately say the booming is almost gone. Its still there but very faint. The buffeting or vibrating sound of the roof is not as bad but I think it still needs more work. All in all so far I would say 85% of the boom is gone and 50% of the buffeting is gone.

  • Like 1
Posted

^^^^^ Jimpro. What year and model do you have?

 

I just started the process to have the THIRD one of these bought back under the CA Lemon Law. Can't take the booming and Buffeting anymore. Which in itself is bad enough, then having to deal with GM Corp BS. New Toyota Landcruiser here we come!

 

Interesting fact I learned from our lemon law Atty. do you know that GM customer service And the GM early response team ARE NOT GM EMPLOYEES? These are outside companies that GM have hired / outsourced to deal with all of us on these issues. So these people we've all been talking too have no skin in the game so to speak. Ya think they really care ?

Posted

I hate to not have specifics but I dont. Even on my service ticket it doesnt say what they did. I was just told by the service manager what they did. I took it in for the booming and buffeting. The service manager and I know each other real well by now. They have had it on several different occasions for other issues Ive had with it. This thing has been a gremlin for noises. This specific time I took it in for the booming/buffeting. Other times have been rearend whine, whistling noises, vibrations. The booming/buffeting has always been there but it was very faint and kind of last on my list to address. After a recent oil change/ tire rotation it got very bad. They had it for a week and kept updating me daily that they were still trying to find the source. Near the end of the week they called and told me they had an updated muffler they took off another vehicle and tried it on mine and they were kind of floored by the difference it made. They told me they were going to order the updated one for mine and it had to come from GM and it might take a couple weeks to get. Then the next day they said GM told them to leave it on mine and they would order the replacement for the other vehicle. When I picked it up I asked if they took it off a new one on the lot and he said no it was ordered for another customers vehicle who has having the same issues as mine. Maybe a picture would be worth a thousand words. Ill try to take some and post them so we can compare. Ill try to get more answers from the dealer as well. After a couple weeks of driving it I can definately say the booming is almost gone. Its still there but very faint. The buffeting or vibrating sound of the roof is not as bad but I think it still needs more work. All in all so far I would say 85% of the boom is gone and 50% of the buffeting is gone.

Also interested in the model/year/engine size since the exhausts are different for 5.3 vs 6.2.

 

Also what dealership were you working with?

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