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Posted

I definitely think there are three things at play. First, I definitely believe that everyone hears things differently. Some people might not even hear what we are hearing/feeling. Humans are different. So it's not that unexpected that we would all hear things differently, including how sensitive to certain noises we each are.

 

Second, I believe everyone has a different threshold to what would be an annoying noise. There could be a whole group out there that hear it, but not enough to be annoyed by it. Might not even register.

 

And third, there are lots of people that don't bother to do something about it, even if they do hear it and even if it does annoy them! They know the dealer and/or manufacturer will give them the runaround and so they just don't bother. And they certainly don't spend time on a forum.

 

So all tolled, who really knows what the stats are. I still firmly believe all the vehicles do it, by the time you account for the variability in severity and the variability in the owners as noted above, the numbers of complaints GM has to deal with works in their favour. Like a war of attrition....the manufacturer always wins!

 

Another way to look at it is with hi end audio equipment. Only a small percentage of people can really hear the difference between $500 and $5000 speakers, or a $500 amplifier vs a $10,000 amp. Same here.

 

So yes, we "buffeters" have unique hearing. (And I'm not saying better!!)

 

There's an old saying...."ignorance is bliss". I sure wish I was ignorant to this issue!! LOL!

 

I would agree with this...My neighbor has a 2015 XL Denali with 20" wheels. Hers buffets but she doesn't hear it. I have driven it and I hear it.

Posted

Has anyone with a buffeter ever driven one that is perfectly fine? Do they really exist or do all of them have it to some degree as some of you have suggested?

 

Sent from my SM-G925W8 using Tapatalk

I have a 2016 that I believe drives fine, no buffeting. It does have a slight vibration when in V4 at times (kind of feels like a manual transmission bucking a bit when the rpms are too low) but other than that it is very nice to drive.

 

I travel between San Francisco and Eugene OR if anyone wants a test ride. Maybe I don't hear the buffeting or maybe it is one of the vehicles that is OK? Test rides would have to be around either Eugene or SF as I don't stop along the way.

 

Jim

Posted

I'm of the opinion that the vibrating and the buffeting are two completely different issues.

 

The tire replacement, re-balancing and an axle replacement made a significant improvement to my vibrating, right up to 100mph. The truck drives smoothly, 99% of the time. I no longer have any vibration issues.

 

In regards to the buffeting, here is my description:

 

  • Single instances of "the boom" at low speeds over bumps [driveways, expansion joints...]; coincides when rear wheels go over the bump; sounds like somebody flicking a 12" subwoofer with their finger; doesn't always happen; commonly heard on concrete borders between driveways/lots and roads; always noticeable on gravel or brick roads; sounds like it's coming from rear of the vehicle
  • Repeated instances of "the boom" at speeds of ~65km/h and ~115km/h [40mph and 70mph]; not heard at speeds greater than 130km/h [80mph]; this is the "buffeting"; annoying as hell; sounds like driving with rear windows down; sounds like double bass from a heavy metal band using a broken amplifier; 30-70Hz range; not all the time, but most of the time; some road surfaces, even smooth ones, seem to excite it more than others; can be heard more clearly when ear is facing rear of vehicle; fades in and out; happens with seats up, down or folded; more audible from front seats; sounds like it's coming from rear of the vehicle; not all humans can hear it

The buffeting sounds exactly like the description of Helmholtz Resonance or "Side Window Buffeting", except that our windows are all up/closed. It's not a new design issue.

Mechanically, there is no model or option that is more prone to it. For example: I've got a short wheel base, no sunroof, running on 20's. And it buffets.

  • Like 1
Posted

I have a 2016 that I believe drives fine, no buffeting. It does have a slight vibration when in V4 at times (kind of feels like a manual transmission bucking a bit when the rpms are too low) but other than that it is very nice to drive.

 

I travel between San Francisco and Eugene OR if anyone wants a test ride. Maybe I don't hear the buffeting or maybe it is one of the vehicles that is OK? Test rides would have to be around either Eugene or SF as I don't stop along the way.

 

Jim

 

I hear/feel the V4 mode too, but it's perfectly acceptable IMHO. It's almost like a light drone. I can hear the difference between the two and often just switch to manual mode to eliminate AFM when I'm trying to isolate the buffeting.

 

We've got some buffeters in the San Francisco area, no?

Posted (edited)

I still am not sure I understand, can you hear this at all, or is it something you just feel? How bad can it be, several people here got a full refund and when right back out knowing the issue was not resolved and bought another one. This defies logic. And has anyone experienced this in a 2016 built in the last 6 months. This entire thread seems mostly devoted to people dealing with their 2015 model year SUV's. Because if GM has figured it out and fixed it, they will do it quietly during production and not admit it then only fix complaints.

 

Currently in a rental Tahoe:

 

2016 LS, September 2015 Build/18" wheels, Goodyear Tires

 

Vehicle low speed/rough surface body booming is worse than my 2015 LT with 20" wheels and Continental Tires

 

Buffeting is about the same.

 

 

In my experience they all exhibit body booming. The buffeting (which I agree with Fog -- is essentially rapid body booming) will vary with the amount of vibration in a particular vehicle due to wheels, tires, drive-shaft, etc. If you can minimize the vibrations, you will minimize the buffeting. I do not believe there are any boom or buffeting free trucks.

Edited by yukontruckman
  • Like 1
Posted

I purchased a Suburban about a year ago and we have the same noise problem. Early on, I took it to the dealership and had a service technician ride in the car with me. He did hear the noise and followed up later that it is when the car drops down to 4 cylinders to conserve fuel. He said it cannot be turned off and there is nothing they can do about it. This makes sense because it occurs in the 35 to 45mph range and the 50 to 53mph range at a constant speed and the engine drops to 4 cylinders. If you are going over 60 mph the car doesn't drop to 4 cylinders and you don't have the noise. The worst part is that ours is getting worse. We were driving the other day and it was so loud that it caused our keys in the cup holder to vibrate and rattle. I have family members that have a Suburban and a Yukon. Neither is as bad as hours but they do have it. I think the Suburbans are worse because of the car weight and our particular car may be worse because we have the larger wheels?? I find it hard to believe that Chevrolet is producing and selling $70,000 plus cars with this problem. I switched from a Navigator to the Suburban and was initially very excited about it but now I regret my decision. It is going back for servicing this week and I have told them the problem is getting worse but I am certain they will come back with "nothing can be done." Hopefully, if enough customers complain, Chevrolet will have to address it.

Posted

I still am not sure I understand, can you hear this at all, or is it something you just feel? How bad can it be, several people here got a full refund and when right back out knowing the issue was not resolved and bought another one. This defies logic. And has anyone experienced this in a 2016 built in the last 6 months. This entire thread seems mostly devoted to people dealing with their 2015 model year SUV's. Because if GM has figured it out and fixed it, they will do it quietly during production and not admit it then only fix complaints.

My 2016 Denali has all the bad habits. Been serviced many many times. GM trade assistance in the works.

  • Like 1
Posted (edited)

 

I would agree with this...My neighbor has a 2015 XL Denali with 20" wheels. Hers buffets but she doesn't hear it. I have driven it and I hear it.

 

I agree...My wife rarely notices the buffeting in our 15 yukon XL while I get a headache during any lengthy drive. One of my three kids complain of it and say his ears pop occasionally while the others don't seem to notice anything. It seems that my wife only notices when it's at its worse which is V4 mode and when on a rough roads which goes back to vibration and how the cabin reacts to it being the main culprit.

Edited by ajs800
Posted

I asked GM Engineering to prove to me that the Yukon XL that is ready for me to pick up that was built at the end of November, just a couple months ago if GM has positively solved these issues. I linked this thread along with the CBS news report and a couple others. This is his answer, what do you all think?

 

John,

 

 

 

A few of those articles are made for media attention… I’ll just leave it there.

 

 

 

The roof boom issue was mostly caused by dimensional variation that created a gap between the roof bow(s) and the roof panel. That gap reduces the rigidity of the roof which can lead to it fluttering at highway speeds. That fluttering turns the truck into, for lack of a better description, a giant drum. That problem was fixed prior to your truck being produced.

 

 

 

One of the articles goes on to mention several other supplier/quality issues that we’ve had which cause vibrations in the truck… These are mostly unrelated, but do manifest themselves in a similar noise/vibration at highway speeds.

 

 

 

Our dealership are full of highly trained technicians. If you have any issues with your truck that they can’t fix please let me know.

 

 

 

All I ask is that you keep an open mind with our product and don’t let the various articles sensitize/sway your opinion.

 

 

 

-Scott

Posted

I agree...My wife rarely notices the buffeting in our 15 yukon XL while I get a headache during any lengthy drive. One of my three kids complain of it and say his ears pop occasionally while the others don't seem to notice anything. It seems that my wife only notices when it's at its worse which is V4 mode and when on a rough roads which goes back to vibration and how the cabin reacts to it being the main culprit.

 

I can barely hear the buffeting in the 2nd row. My 3 kids can't hear it, even while we're in the sweet spot and I ask them to actively listen for it.

 

I can't hear the buffeting in the 3rd row. My dog refuses to tell me if he hears anything.

 

Passengers in the 1st row either hear it immediately, have to actively listen for it and others don't hear it at all.

 

It could be psychological, but the buffeting seems worst in the drivers seat.

Posted

I asked GM Engineering to prove to me that the Yukon XL that is ready for me to pick up that was built at the end of November, just a couple months ago if GM has positively solved these issues. I linked this thread along with the CBS news report and a couple others. This is his answer, what do you all think?

 

John,

 

 

 

A few of those articles are made for media attention… I’ll just leave it there.

 

 

 

The roof boom issue was mostly caused by dimensional variation that created a gap between the roof bow(s) and the roof panel. That gap reduces the rigidity of the roof which can lead to it fluttering at highway speeds. That fluttering turns the truck into, for lack of a better description, a giant drum. That problem was fixed prior to your truck being produced.

 

 

 

One of the articles goes on to mention several other supplier/quality issues that we’ve had which cause vibrations in the truck… These are mostly unrelated, but do manifest themselves in a similar noise/vibration at highway speeds.

 

 

 

Our dealership are full of highly trained technicians. If you have any issues with your truck that they can’t fix please let me know.

 

 

 

All I ask is that you keep an open mind with our product and don’t let the various articles sensitize/sway your opinion.

 

 

 

-Scott

 

 

I'd say he is full of shit. Media attention? Does he think we like driving a vibrating ear-popper around town, especially after dropping 75k on it? Media attention would be me standing in front of GM's headquarters with a sandwich board around my neck asking folks not to buy a Yukon. We aren't quite there.........yet.

  • Like 2
Posted (edited)

[GM Engineering wrote:] The roof boom issue was mostly caused by dimensional variation that created a gap between the roof bow(s) and the roof panel. That gap reduces the rigidity of the roof which can lead to it fluttering at highway speeds. That fluttering turns the truck into, for lack of a better description, a giant drum. That problem was fixed prior to your truck being produced.

 

My roof was recently dismantled and the gap between the roof bows was fine - within specs. No issues found. They added material [adhesive or insulation?] anyways, just to be prudent.

 

No change. My Yukon still buffets at 40mph and 65mph.

Edited by FogDucker
  • Like 1
Posted

 

 

I'd say he is full of shit. Media attention? Does he think we like driving a vibrating ear-popper around town, especially after dropping 75k on it? Media attention would be me standing in front of GM's headquarters with a sandwich board around my neck asking folks not to buy a Yukon. We aren't quite there.........yet.

 

 

Actually, that is exactly what the problem looks like to me. The roof wants to pop up and the glue simply cannot hold it down, at least not for very long.

 

I am perfectly Ok with keeping an open mind. I really do like everything else about the truck. I just need this issue fixed.

 

Frank

Posted

This is getting buried in the pages

 

There was a member here who took the time to sit in each position and gauge the "issues" - by far and away, the drivers seat is the worst seat in the house while "feeling" them in the 2nd and 3rd row is almost non existent

 

So taking a tech as a passenger is not the best way for them to experience the issue

Posted

This is getting buried in the pages

 

There was a member here who took the time to sit in each position and gauge the "issues" - by far and away, the drivers seat is the worst seat in the house while "feeling" them in the 2nd and 3rd row is almost non existent

 

So taking a tech as a passenger is not the best way for them to experience the issue

That was me. I believe that others observed the same thing.

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