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Posted (edited)

LSUMatt1514 - Not a stupid question, you are correct with all are not experiencing this issue, data in earlier pages. This is all we know, everything else is speculation. You can provide some data though, drive a base model of the Yukon and Tahoe and post your results based on knowledge of this thread. Base models are definitely different, could provide good data (smaller wheels/tires, no ANC, smaller engine in some cases, sound system set-up)

Edited by The Zip
Posted

20sierra14 - Most posting here have 22's, but your vehicle with 22's does not S/V. Are you running aftermarket or OEM wheels? Was there any additional service to your wheels?

Posted

20sierra14 - Most posting here have 22's, but your vehicle with 22's does not S/V. Are you running aftermarket or OEM wheels? Was there any additional service to your wheels?

Nothing.. Stock Denail Q7M wheels.

Posted (edited)

Your reply infers something could be wrong with the wheels on vehicles experiencing S/V, especially if they are running stock Q7M like you. When any of my vehicles experienced S/V, out of alignment wheels was the first place I looked. This was the case in every instance. 50 bucks at a local tire shop is a small price to pay if this mitigates the S/V. These days, out of alignment wheels is logical and should be common, more wheel and less rubber on the road. I'll ask my local tire shop the question.

Edited by The Zip
Posted

Zip,

are you in the SLO or Monterey area? We ordered a Denali and it's currently on the train to the LA area. It should be at the Seaside dealer late next week.

Posted

20sierra14 - Does the mic wells have finite space? If not, you would have used more cotton balls. 2.5 cotton balls, the space is pretty small but the result is big. Schematics show mic locations, but gives the appearance they are not enclosed. How much does your headliner move or flex, or does it?

Posted (edited)

Over the weekend, I am going to check the lower right rear of the engine block, schematics identify NKC at that location. I've known this for a while, but my specific issue didn't require me to research outside the passenger cabin. NKC (better known as ANC) at that location could compensate for engine gearing, V8 to V4 transitions, and external noise caused by uneven terrain. Not even a guess here, I need to read some more.

Edited by The Zip
Posted

I have a new 2015 Escalade ESV (purchased October 2015 and built in Arlington) and it started the buffeting sound about 1 month ago. It now has approximately 6000 miles on it. The effect is getting worse every day and physically hurts my ears going over a railroad track. Before we purchased it we test drove a denali and the buffeting was so bad, even the salesman who was riding in the back noticed it and thought it might be the tires, so we got another one and tested it and we did not hear it, but we still ended up choosing the escalade. I have an appointment in 3 days with our dealership (not same dealership as where it was purchased) and I am curious to see what happens after reading all these posts. Not that it matters - but I am an attorney and own a 5 lawyer firm, so hopefully it won't get that far, but this problem seems to be very widespread. If I have missed anything and should be telling them something, please let me know (there are 40 pages on here - so it's entirely possibly I missed something important). Thanks for all the information!!

Posted

romanbasi - if you read the posts, you didn't miss anything. Your dealer will say something like this is the first I've heard of this but I will work with you. This thread is past that point. Tell your dealer to disable/disconnect all “three” passenger cabin mics and give you a call to test drive prior to doing anything else. In the meantime they could get up to speed with reading the thread.

 

wrench589 - your comment, "Is that a microphone, or some other sensor in the engine compartment"? Mounted to the engine block?" I'll tell you what I know in accordance with data; the passenger cabin mic pins that lead into the audio amp is right next to this specific pin. Relation seems logical, same name same pin grouping. Relevant, don't know.

Posted

So Finally the YUKON Is gone and we recieved every penny back from GM. This took 6 weeks from getting the green light from GM for the buy back.

On the Escalade, I wanted to do the cotton ball testing. But am reluctant to remove the grills, don't want to break them. So yesterday I placed two pieces of thick masking tape over each of the three Mic's. LoL.... Has anyone tried this? I didn't notice any improvement at speeds under 50 on surface streets. Then jumped on the freeway. Was driving around 70mph and heard some loud Fast and Furious street racer car around me with his loud exhaust system. Couldn't see him...... It was the Escalade !!! This was unbelievably loud in the cabin. I pealed off the tape above my drivers side grab handle, the the exhaust tone stopped. Put it back on, gave it a little gas and the LOUD simulated exhaust tone returned. Has to be triggered by throttle sensors??

Taking the kids to school this morning, just shaking my head as this thing is such a total P. O. S ! The thing feels like it's running out of gas whenever it switches over into V4 mode. You can feel and hear the whole truck rumbling. The gas pedal has a spot where it feels like it all the way down, then if you continue to push it has 50% more throw available. Every bump in the road makes this thing omit the booming subwoofer sound. How can something so nice be such a piece of junk? The suspension is so incredibly over firm. This has to be part of the problem??

 

SHAME ON YOU GM FOR MAKING YOUR CLIENTS GO THOUGH ALL OF THIS !

 

I only Wish my wife didnt love these things. I would Like nothing more to be rid of this whole ordeal ! Wish I found this thread back in September before I sold my flawless TOYOTA TUNDRA and bought the first Yukon. The time, and money I've spent on all this is so incredibly stupid.

Posted

Tobtek - this thread is past folks beating themselves up over this issue. Look, you've already spent 80K on that truck, those grille covers probably cost maybe 10 bucks. Pop those freakin covers and stuff 2.5 cotton balls in the mic well, cover with tape and provide an assessment. This is a proven mitigation measure to minimize the buffeting, how well this mitigates would depend on whether or not you have shaking or vibration (S/V)

 

We are at the point in this thread how to improve on that mitigation measure. I have an idea how to improve on the cotton ball and tape concept, but I need more information before I can proceed.

 

I respectfully say again to everyone experiencing the buffeting, pop off the grille covers, drop in 2.5 cotton balls, cover with tape, provide results, then standby.

Posted

I realize all makes and models have experienced the buffeting issue, but it seems the longer wheelbase (Suburban, XL & ESV) are the majority of the complaints. Perhaps the effect is more pronounced with the larger cabin.

Posted

2015 Tahoe, LTZ with the 22's Same issue as the above GM patrons but primarily at 40-50 MPH. The dealer indicated to me today, the steel support beams supporting the roof needed to be re-bonded to the sheet metal and the tech added 3M vibration damper to the same sheet metal. Once complete, they will "road force balance the tires" and they expect this to cure the problem. SB completed by Monday.

I am cool with this if it cures the issue and there are no structure/safety issues. However, the decision maker (my wife) is 100% adamant about going back to her Toyota Seq.

More to follow on Monday.

 

Thanks for all the posts

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