Anon2015

It's sad GM walked away from this issue. Other than being skeptical about small turbo charged engines, I do believe Ford just torched GM with the Expedition...better thoughtful design, better technological features, better sound system, and comparable price points.

Jack...you must bring this matter to both your dealer and to the GMC CustomerNoCare group if only to go on record at your current mileage.

So, according to GM, 40 engineers working on the problem. Here's how that gets decoded: 1. The Engineers know what the problem is and have a fix; 2. The spreadsheet lads are saying no, no too expensive find another way; 3. The ivory tower hasn't decided who to blame and then suggest an alternative career.

My suggestion to anyone who just must have one of these vehicles is: 1. If you order it, you make acceptance contingent upon not your truck not having these issues ... (do not accept 'covered under warranty'). If the dealer refuses, you didn't want to do business with that dealer in any case. 2. If you're going to buy off the lot, then the sale is contingent upon a 24 hour test drive and none of these issues occurring during the test drive. Again, if the dealer says no...find another dealer or look at other brands.

It would also work to file a complain with www.ftc.gov/about-ftc/bureaus-offices/bureau-consumer-protection

That response is a tad bit on the rude side, is inappropriate and not needed. The only way the full force of GM will ever get applied to resolving this issue is for everyone who has this problem, or who has had the problem and resolved it only by means of purchasing a different make/model is to (1) report the issue to the NTSB; and, (2) to the Federal Trade Commission Bureau of Consumer protection. www.ftc.gov/about-ftc/bureaus-offices/bureau-consumer-protection None of us are GM customers. We are customers of the dealer involved ... all of whom have been pretty much hung out to flap in the breeze by GM.

"Mine has been measured with the Picoscope as we'll. all it showed was the vibration was at the wheel / tire frequency so the did a Roadforce balance. 2 tires out of spec so 2 on order. But, they did Roadforce first time I took it in and after adjustments, all 4 were brought in spec. So, after some use, 2 tires went out of spec. Just like the pickup owners are experiencing. " Here's the problem with that. The vibration was traced as coming from the tires unfortunately that doesn't determine what caused that issue in the first place.

The fact you have a vibration is one matter. Determining the source, or fault, which causes the vibration is one of the many diagnostic functions of a picoscope. The fact you have a vibration is one matter. Determining the source, or fault, which causes the vibration is one of the many diagnostic functions of a picoscope.

Congratulations to GM! Not only can they misrepresent vehicle features, execute sloppy engineering and provide zero customer service, the Tahoe/Yukon/Escalade has won a spot on Consumer Reports 20 most unreliable vehicles. Way to go! At least they are consistent.

To my knowledge, GM has never placed one of these problem vehicles in a wind tunnel. That would definitively determined if the problem is mechanical or induced by air flow around the vehicle (vibrating panels).

"Now, both Chevy and GMC show that the 9 and 10 speaker Bose systems include the "AudioPilot" Noise Cancellation feature. " AudioPilot and ANC are two different beasts. Active Noise Cancellation (ANC) is an effort to reduce cabin noise and can only work effectively at low frequencies (a function of cabin size and seating area size). AudioPilot is an attempt (a poor one at that) by Bose to increase the intelligibility of (in particular, speech) sound from your radio/audio system. It measures cabin noises by frequency and then boosts those frequencies masked by cabin noise.It does not work across all bands and its effect is very difficult to discern...and difficult to detect without some rather sophisticated analysis equipment. Both were developed by Bose. Magnetic Ride Control was developed by GM and can be found in the Audi R8 and Ferrari. Bose has also developed a much more sophisticated Magnetic suspension. There were rumors Bose and GM collaborated on the system use in the Yukon Denali and Escalade. Based upon performance, it would appear to be just that --- rumor. Also based upon performance it would appear to be the older single wire system rather than the two wire system on the Corvettes...I guessing on that however.

Note: In addition to the consumer magazines, each of you with this problem should submit your problem to BBB Autoline and the Federal Trade Commission (yes, they do want to know). Let me add some input on this. GM/GMC has done several things in the past 18 months, which are unethical, and in some cases illegal. Two examples (most commonly found in this and other forums): (1) these vehicles have a problem with buffeting which has caused headaches, makes many unable to be in the vehicles, and caused symptoms of vestibular disorientation ... in the best case, discomfort and in the worst the disorientation, need to vomit, and severe headaches could be a distraction leading to an accident; and, (2) continuing to market the vehicles as having a lay flat cargo area which it is not, leading to items falling out of the vehicle when the tailgate is opened and, in one case, a heavy item falling out and causing personal injury. In both of these examples, GM/GMC has (a) acknowledged these issues, is continuing to advertise, market, and sell the vehicles without warning consumers of the potential problems; (b) has no solution to either problem; and (c ) is unwilling to take back vehicles with complete refunds to consumers or in many cases, simply doing nothing except perhaps offering a $250.00 to $1000.00 coupon to purchase accessories (for a vehicle you don't want to keep). Unless GM/GMC starts getting pressure from BBB Autoline and the FTC, they have absolutely no incentive to fix the issues or, in some manner, compensate the owner, or replace the vehicle (no charge to owner). My 2 cents only.

"My Yukon is a stock 2015i short Denali with the only option being the 2nd row bench. No sunroof. 20" wheels with Continentals. 6.2L/8-speed" For the record, my daily driver is the same but with the sunroom and crossbars.

I did not have this specific problem with any of the three '15 Yukon Denalis (1 - 2015, 2-2015i). Other issues? Oh yeah. For example, after two software updates, the 8-speed still doesn't shift correctly.

When the seats were put down for the first time they were neither flat or even with each other. Back to the dealer...yup, not right, we'll fix it. I'm not the only one to discover this after the purchase. Being told it would be easy to fix turned out to not be so true. I'm sure the circumstances behind many of the purchases of these vehicles with the buffeting were under similar circumstances ... so you didn't drive your vehicle before you paid for it? Maybe it was a special order like mine. EDIT: ... all three of mine.

If you read this post: http://www.gm-trucks.com/forums/topic/169098-does-anybody-like-their-new-rides-here/?p=1688349 you'll see GM is taking much the same attitude as with this problem. Doesn't matter how we (GM) market or advertise or what we (GM) know when we (GM) sell these vehicles to our dealers ... the problem is engineered in so take it or trade it in. Note you are not GM's customer ... the dealer is. You get to pay 60k to 90k for a vehicle with engineered in problems so you can drive it around advertising GM's product.

Most of those publications would not dare publish, or further research, the issue unless the article would be favorable to GM ... they make too much revenue from GM to bite the hand that feeds them. I would suggest you provide that information to Consumer's Reports.

'Bottom line, it's a bit of a POS' Being a tad kind ... more like a big pile of do-do

That's interesting, Wrench. Mine does cover that topic. (I do cheat however ... I downloaded the PDF version for full text searches). Page 9-21. ACC/ACCESSORY (Amber Indicator Light): This mode allows some electrical accessories to be used when the engine is off. With the ignition off, pressing the button one time without the brake pedal applied will place the ignition system in ACC/ACCESSORY.

None-the-less, the answer is found in the user manual. The inability of one to read is outside the scope of the question.

I have owned 3 2015 Yukon Denalis. One an early production model and two 'interim' models. None had this issue. I have not found a vehicle known to have the problem I could test and measure. That is not to say the problem does not exist ... it most certainly must; however, I suspect it is in part the vehicle's engineering and in part individual sensitivity to the intensity and frequency(ies) involved.

I am very much aware of that, although it is not about pressurization; but rather pulsing (or buffeting). Simple pressurization is Ok ... as in commercial jet aircraft. Related concerns have been mentioned with respect to other 'noise' matters. Thanks for your concern.

I think GM needs to have a chat with the lads at Rolls Royce. There are complaints from chirps, to squeaks, to rattles, to diodes humming a tune ... What GM engineers failed to understand is that as you lower the noise floor in a vehicle, you will now hear stuff nobody had a clue ever existed.

It is a mystery as to why GM still has that TSB active. Their rate of success following that method to-date has been zip.

Salt water bags would not be increasing the number of modes; however, due to their absorption of low frequencies, any modal response at those frequencies would be reduced in amplitude. Also, note, modal frequencies are a function room (or cabin) dimensions. While modal response is a form of resonance, it is not the only cause of resonance. The more likely source of the booming/buffeting is from mechanical resonance (drive train, engine, exhaust system, etc). From the work by Wrench, the predicted modal frequencies (derived from the dimensions of the cabin area) are not the problem frequencies as measured.