Zig10

Anyone tried mounting a rooftop luggage box and seeing if it makes a difference? If it were just a matter of stiffening the roof it would be a pretty simple matter to add intermediate support between the existing bows. They already have these guys pulling the headliner and rebuilding the bows, all you'd need to do is add some lattice connected in between, like reinforcing a joist bay. Since the movement is so miniscule, it wouldn't take much. That said, I have to think that the engineers on this have tried that. It would be the first thing in mind for a vibration or deflection issue. This has to be deeper than that, or after 2 years of working on it they wouldn't still be throwing darts at the issue and wasting money on fixes that don't seem to yeild too many positive outcomes. Speaking of which, my dealer has moved on to tearing apart the differential in my car. No word back on whether or not it has helped, or if it is out of spec. Never thought I would feel like this much of a dumbass for purchasing a vehicle...

They're not going to outlast customers in states with solid Lemon Laws. They can keep replacing vehicles until an owner finds a satisfactory one, or spend a lot on lawyers and forced buybacks until it starts to erode the profitability of the line, at which time a solution will need to be found. The beancounters won't let it get too far gone as these are currently among the most profitable vehicles in GM's lineup. The question is, how many people notice the issue and just deal with it VS. those who raise a fuss about it, and is it enough to tip the scales? I have no intention of taking this vehicle back until the issue is rectified. If the technician is bothered by it, then I am pretty sure the situation is still pretty bad.

Anybody got a GoPro and a good magnet?

Within about 10 seconds of hitting 40-45. Normally it's jsu an annoyance, but if you have a cold with any kind of sinus pressure it becomes pain-inducing in your ears...or at least in mine. My family has been passing around a head cold for the past 20 days or so, and I haven't been able to drive that car for more than a 5 minute trip to the store and back. The loaner they gave me is a base-model V6 Sierra SLE pickup. It drives pretty poorly and doesn't have enough power to get out of it's own way, but no pressure issues of vibrations of any kind. Sad that I am making payments on a $70k vehicle, stuck driving a $45k vehicle, and somehow this is a better driving experience. How in the hell does GM think that this is acceptable in any way?

The drone was a separate sound, and one I am familiar and ok with. One of my business partners bought a new Tahoe about 2 days before I got my Yukon. I drove his against mine back-to-back to see if the buffetting was there. His was fine. There was some drone in 4 cylinder mode, but no pressure sensation at all.

Yup.

Well, just got an update from the dealer. After a week of working on it to ensure that the required PI from GM was followed to the letter, the tech drove it this afternoon and the buffetting was still there at 40-45. They did say that the issue at 65-70 was gone, but that was never as bad to begin with. I am so disgusted right now it is not even funny.

Oh, and I am running factory 20" wheels. Sorry I missed that earlier.

I gave them the contact info for Frank's dealer and asked them to call to review their process. I am doubting they called, though. According to the service manager this was the first issue they have had with this, so they sent it to a local body shop for the work. It's all a little loose for my taste. If it doesn't work, I will be back in touch with GM (I have a case number), and we'll see where it goes. This whole thing is just giving me a headache...from the pressure when I drive that car, and from the stress and frustration dealing with this.

Forcing functions. I just had a flashback to my systems dynamics class from junior year...nearly two decades ago. Ugh. Anyway, my Yukon has been at the dealer for 3 days now for the roof bow fix. I was told it would take 2, now we're heading towards 4. I hope this is just because the body shop got backed up and decided to take their time, and not because the fix didn't work. Still keeping my fingers crossed.

Well that should be an interesting article. Wonder if he spoke to GM as well?

Just thinking out loud, wouldn't that mean that the drone is present any time the vehicle is in that same RPM range? And why would it only occur between 40-45 MPH on a vehicle (at least on mine)? I have to admit that I did not try shifting to a lower gear at those speeds, but if it is an exhaust back-pressure issue then running the engine at a different speed should solve the problem, at least temporarily. I'll have to give that a try.

So is there an adjustment that can be made to pull it in? The tolerances can't all be THAT bad that there is a 3/8" - 1/2" difference in tightness on the glass from one vehicle to another.

Man...I wish I wouldn't have looked at those pictures. Mine goes in to the dealer next week (again, they had to order the parts) and I am just feeling queasy over this right now. $70k to tear a car apart with 1000 miles on it. @#%&!!!

If it was done properly, I would imagine it would hold pretty well. Filling the gap in between the spaces alone should keep the roof from flexing as much simply because the contact points limit the reactive length of the panel. The glue would be under less stress, and it should all work as designed... Of course, it should all have worked as designed from the FACTORY, so take it all with a grain of salt. I think it is a bit unreasonable to expect mechanics to be doing body panel work and get it right, especially when the assembly line can't keep the tolerances that are required BEFORE any of the electrical and HVAC equipment goes into the roof area. It's got to be a complete PIA working up there after the fact. Well, fingers crossed. Mine goes in this morning...

First time poster here. I have 850 miles on my 2015i Yukon XL SLT and first noticed the pressure / booming at about 200 miles. Mine only seems to have it from 40-45 MPH, though it does have an annoying highway vibration as well. Fortunately no pressure at those speeds. Taking it into my dealer this coming week and have already forwarded them this thread. The service manager said this is the first one they've had in for the issue, but said he is willing to try anything to make it right. Frank, can you PM me or post the info for your dealer that was able to fix your vehicle? I would like to get them talking if possible. What a PIA for a brand new $70k vehicle.