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Posted

Tobtek, have the rear end gears been replaced yet? For what I'm seeing on the tahoeyukon.com forum, replacing the rear end gears is the only thing that has worked (twice, so far) to eliminate the buffeting/drone/pressure problem.

 

My take is that there is something NG with the original gear sets that is the root cause of the buffeting/drone/pressure. But, the overly stiff shocks makes it even worse. Fix the shocks and the harshness goes away, as does some of the buffeting/drone/pressure, but also need to have the gears replaced. And, by the way, need to have both rear and front done. One of the folks on the pickup truck forum dealing with the "vibration" issue noted the dealer changed the rear end gears and the vibration went away....until he put it in 4wd! I notice more vibration in the steering wheel in 4wd. And, the vibration is the root cause of the buffeting/drone/pressure, I think.

 

Replace shocks and both gear sets, and we might just be out of this mess!!

Posted

I'm not sure if this is good news or bad for those of us with this issue. I did a query on SAEs website to see what kind of technical papers may have been written on this kind of issue, if any. I searched for "booming" as the SBs I've found use that term to describe the pressure/noise we are experiencing. Guess what I found?

 

http://www.sae.org/search/?qt=Booming&sort=relevance&sort-dir=desc&display=list&taxonomy=&sector=%28%22AUTOC%22%29&content-type=%28%22PAPER%22%29

 

Hundreds of papers written by those in the automotive industry regarding booming noises in automobiles. I even found a couple of papers on line that mention the pressure sensation associated with these low frequency sounds. So, this issue is nothing new to the industry, and there is lots of science out there. That's the good news. The bad news, is this is a complicated phenomenon, not easily corrected. Complicated even more by the fact that some vehicles don't exhibit it, and some don't initially and then suddenly develop it. Even Jansondenali mentioned that with his second Escalade.

 

Of course, this is way beyond what the dealer can do. This is GM heavy engineering stuff.

 

And, to really make it interesting, check out this write up on the GM Terrain when they brought it out.

 

http://www.engadget.com/2011/02/25/gm-shows-off-terrain-suv-with-noise-cancellation-says-silence-e/

 

So, GM knows all about "booming" noises in the vehicle, especially when running the engine at low rpm's for improved fuel economy. The solution - try to use noise cancelling technology to hid it. Of course, if the noise cancelling system doesn't work well enough, then the noise will still be heard. Of course, that doesn't explain the vehicles that don't have noise cancelling, like the Yukon SLE and SLT's.

 

The plot thickens!

  • Like 1
Posted

Tobtek, have the rear end gears been replaced yet? For what I'm seeing on the tahoeyukon.com forum, replacing the rear end gears is the only thing that has worked (twice, so far) to eliminate the buffeting/drone/pressure problem.

 

My take is that there is something NG with the original gear sets that is the root cause of the buffeting/drone/pressure. But, the overly stiff shocks makes it even worse. Fix the shocks and the harshness goes away, as does some of the buffeting/drone/pressure, but also need to have the gears replaced. And, by the way, need to have both rear and front done. One of the folks on the pickup truck forum dealing with the "vibration" issue noted the dealer changed the rear end gears and the vibration went away....until he put it in 4wd! I notice more vibration in the steering wheel in 4wd. And, the vibration is the root cause of the buffeting/drone/pressure, I think.

 

Replace shocks and both gear sets, and we might just be out of this mess!!

 

 

Total MESS...Yes. But No, they have not touched any of the gears yet. Been dealing with the nice people at the GM Corp office again. Trying to get the authorization to switch out the gears, AND try some softer sidewall tires. I've been in vehicles with over inflated tires, and had similar sounds as our Escalade is producing. ??? While at the service dept this time, Maybe they can fix all the other issues.......I know, wishful thinking.

Posted

Just got wife's 2015.5 Yukon Denali last week and I can't stand the pressure on my ears.. I first was checking the bass on the radio them realized after a while it is the truck. It really annoys me and I don't tell her in case she hasn't noticed it.

Posted

If you are in the market for one of the 2015 GM Fullsize SUV's (GMFSUV), conduct this test first. Drive a GMFSUV(1) non-extended version, base model, 20 inch wheels or less, with Premium Ride Suspension. Then compare the ride to a GMFSUV(2) extended version, bells and whistles, 22 inch wheels or more, with Magnetic Ride Suspension. This comparison is not definitive because most GMFSUVs 1 and 2 are trouble free, but based on input on this thread from "owners", the GMFSUV(2) will more than likely exhibit issues of buffeting and pressure on more occurences than the GMFSUV(1)

 

GM has not figured-out or yet published information to answer problems associated with buffeting and pressure with the 2015 year truck, if you purchase a truck with these problems you will definitely regret it. But if you just got to have one of these trucks, the test may allow you to get lucky and your truck may not experience any issues at all.

Posted (edited)

Just got wife's 2015.5 Yukon Denali last week and I can't stand the pressure on my ears.. I first was checking the bass on the radio them realized after a while it is the truck. It really annoys me and I don't tell her in case she hasn't noticed it.

 

Reference back to the cotton ball trick I did w/ the mics.. It takes literally 10 mins to do.. Since you aren't experiencing buffeting, the pressure can be fixed by deafening the mics.

 

Edit: I'm going on 8 weeks now w/ no pressure.. I did have to replace the cotton balls w/ fresh ones, but so far, it's worked perfect for me.

Edited by 20Sierra14
Posted

 

 

GM has not figured-out or yet published information to answer problems associated with buffeting and pressure with the 2015 year truck, if you purchase a truck with these problems you will definitely regret it. But if you just got to have one of these trucks, the test may allow you to get lucky and your truck may not experience any issues at all.

I was running the other day and a Tahoe was coming towards me up a small hill. As it got closer I could hear a kind of humming/droning sound like it was lugging before changing gears. Has anyone else heard something like this outside the vehicle?

Posted

Hi all, I'm new to the forum.

 

My wife and I have been loyal GM customers for quite sometime now. In particular, my wife has gone from Equinox to Envoy to Yukon to Suburban to her first NEW 2015 Suburban LTZ, which she slapped down 70k for.

 

What a disaster. She's had the car for less than a week and cannot stand the vibration inside the cabin. Her ears (and mine) experience the pain/pressure like so many others on this forum. I can't have my kids in this car!

 

In addition, apparently the new engine is much louder than the older models. She traded in an '08. The 2015, apparently because the way the new engine is made, maybe because of electrical components, makes a ticking like noise at idle. Disappointing, but bearable.

 

We just called the dealership today, and left a message for the manager that we will likely be having them buy the vehicle back.

 

With this looking like an issue with Cadillac, GMC, and Chevy, what the heck are my options for a large SUV? We have 4 kids, and my wife WILL NOT drive a minivan. Are my only options to go used? If so, how far back do I need to go to find something without this vibration issue?

 

Thanks all!

Posted

Dadof4 - Unfortunate that this is your first post, hope everything works out at the dealership. I own a 2015 and 2001 model and just got rid of my 2008 model. My '01 and '08 generations did not have any issues associated with this thread, neither does my '15. I don't have knowledge to comment on other manufacturers Fullsize SUVs, but for GM, you may not have to go back any further than the 2014 model if GM ends up being your option.

Posted

Or you could try a loaded Traverse LTZ if your dealer will work with you. My wife has the Acadia, and it seats 7. Drives like a car, but it won't tow like a real SUV (thats what the Avy's for).

Posted

Hi all, I'm new to the forum.

 

My wife and I have been loyal GM customers for quite sometime now. In particular, my wife has gone from Equinox to Envoy to Yukon to Suburban to her first NEW 2015 Suburban LTZ, which she slapped down 70k for.

 

What a disaster. She's had the car for less than a week and cannot stand the vibration inside the cabin. Her ears (and mine) experience the pain/pressure like so many others on this forum. I can't have my kids in this car!

 

In addition, apparently the new engine is much louder than the older models. She traded in an '08. The 2015, apparently because the way the new engine is made, maybe because of electrical components, makes a ticking like noise at idle. Disappointing, but bearable.

 

We just called the dealership today, and left a message for the manager that we will likely be having them buy the vehicle back.

 

With this looking like an issue with Cadillac, GMC, and Chevy, what the heck are my options for a large SUV? We have 4 kids, and my wife WILL NOT drive a minivan. Are my only options to go used? If so, how far back do I need to go to find something without this vibration issue?

 

Thanks all!

Don't wait. Get your money back ASAP. Get a claim number from GMC customer service to get the ball rolling. There is NO fix for the ear pressure sanctioned by GM. All they will do is rip apart your truck and hand it back to you in worse condition than you received it...with the ear pressure problem still persisting. Trust me, I have been down this road...twice. Just get your money back.

Posted

@dadof4 - With this looking like an issue with Cadillac, GMC, and Chevy, what the heck are my options for a large SUV? We have 4 kids, and my wife WILL NOT drive a minivan. Are my only options to go used? If so, how far back do I need to go to find something without this vibration issue?

 

We are in a similar issue as you trying to find the large SUV for myself and family, since the big mess with GM. After looking for for the last nine months in complete frustration we are considering either 2014 Yukon/suburban (no issues) or 2014/15 FORD Expedition EL (augh) for the room. There is nothing else out there smaller that has the comparable room besides the dreaded mini van. Believe me we have driven them all trying to make something work. Sincerely Wish you much luck with your search!

Posted (edited)

2014 (Chevy) rear shocks are inferior to the current and prior versions, but this is an excellent version. Replace the OEM shocks with quality aftermarket and this truck will get the job done.

Edited by The Zip
Posted

Could this be related to the aero dynamics of the roof? Our last (09 Denali XL) had no noise at all but from time to time I would tow a buddy's enclosed trailer and that would cause an extreme buffeting noise around 40 mph. I could tow other trailers with no noise what so ever. Just has me thinking that if all of the new trucks do this perhaps there is something aerodynamically with the roof line that is causing this?

Posted (edited)

Could this be related to the aero dynamics of the roof? Our last (09 Denali XL) had no noise at all but from time to time I would tow a buddy's enclosed trailer and that would cause an extreme buffeting noise around 40 mph. I could tow other trailers with no noise what so ever. Just has me thinking that if all of the new trucks do this perhaps there is something aerodynamically with the roof line that is causing this?

Perhaps to some degree..... maybe?? Our 2015 i Escalade is most annoying around 20-30 mph going over uneven road surfaces. That would lead me to believe it's more of a tire/shock/suspension issue. The bumps radiate a booming sound through out the cabin. It sounds exactly like the stereo's subwoofer is working on its own. Our Escalade is going back in tomorrow AGAIN for more trial and experimentation. Hoping to try the new front and rear ends, and softer sidewall tires. I Really think the rear end isn't right on ours. Coming to a stop you can hear a high pitch whining sound back there, and if you let off the gas while going down hill the rear end back lashes and slaps the whole truck forward. LoL.. Was dropping the kids off at school last week and it did this so bad, my girls were saying " Dad, why did you have to do that" it's really bad. Has to be something to this! It's sounds like the gears are to tight maybe, not enough clearance or free play??

And of course it's in for the Non Op Nav system, the rear suspension that's still squeaking, the transmission issue that feels like it's in 20th gear when driving slowly, then It usually has a " Chirp" sound back in the exhaust system when giving it a little gas as well. The non op blue ray playback issues. Etc, Etc, Etc......

 

Love this new truck. It's so neat :( ..... What a complete piece of junk!

This whole fiasco should be completely embarrassing for General Motors. I just yesterday completed my JD Powers and Associates survey, would be really interesting if anybody contact me about the comments I left.

Edited by TOBTEK

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