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Posted

Anybody got a GoPro and a good magnet?

Better yet, do this on a dyno so that road surfaces are taken out as a factor.
Posted

If the booming isn't across all vehicles, it's less likely a design flaw and instead defective part(s) or improperly installed parts.

 

Definitely not a design flaw. Two years in to this generation GM is going through the process of finding out which part is defective or improperly installed.

Posted

There is so much speculation in this thread that it is not really useful to a noob like me. I've read so many theories and 'fixes' that did or didn't work that my head is spinning. As a soon to be new owner (2016 Yukon Denali XL set to be delivered mid-January) all I can hope for is that I won't face the issues presented here. Good luck to those of you facing these problems now and I hope they get resolved or that you get out of ownership without losing your ass. Not very confidence inspiring in GM.

Posted (edited)

We need a thread with a head count on who had the problem and got it fixed and what fixed it or improved it. And who had no success and what they tried to fix

Edited by Cl Houn
  • Like 1
Posted

The test drive is key. Don't just settle for the typical 3 mile loop. Insist on 5 minutes each on a highway wide open, crappy roads and regular roads.

 

You want to be able to stay in 35-45 and 65-85 for a few minutes.

 

If it buffets or vibrates, you'll know. In my experience, all boom just find the one that booms the least.

Posted

Have been strongly considering purchasing an 2016 Denali Yukon XL but after reading through these posts I am a little apprehensive of doing so. Will wait and see what happens for now.

Posted

I'd notice it right away too, at the sweet spot speeds and driving over expansion joints. Ditto on the exhaust drone - that's a distinctly different tone which isn't annoying as hell.

If the booming isn't across all vehicles, it's less likely a design flaw and instead defective part(s) or improperly installed parts. Somebody must be able to solve this!

I'd love to be able to visually inspect the underside of the truck while it runs at ~65mph.

My experience has been all the various different ones I drove exhibited the booming/buffeting/pressure, albeit to varying degrees of severity. In my opinion, it is a "design flaw", or more likely a "design oversight". There is something about this SUV platform that is significantly "worse" than others.

 

As I've pointed out before, the phenomenon of "boom" and "drone" is extremely common in vehicles. There are literally hundreds of technical papers addressing it in the auto industry. But, most vehicles it is under control, and hence not noticeable or not annoying. Since dealing with this issue, I have paid attention to all vehicles I drive and every SUV booms when it goes over a pothole or such. But, the sustained booming which becomes the buffeting doesn't happen to them - only the new GM full size. So, there is something about this platform that is either too stiff, or too flexible, or a resonance they missed...or something. Lately, it seems more like a shuddering or fluttering that ends up being the buffeting. And it does seem to come and go, almost like a phasing issue between components.

 

Bottom line, I have zero expectation GM will "solve". This. They will throw some parts at it. New tires. Try to appease the customer until warranty expires. They will win on attrition alone. They will outlast all of us combined. And because this in not a safety related issue, they will invest absolutely minimal resources. In fact, I can almost guarantee that the corporate attitude to this is "fussy customers. There is nothing wrong with this vehicle". That has always been the GM corporate mentality and still is to this day.

Posted (edited)

My experience has been all the various different ones I drove exhibited the booming/buffeting/pressure, albeit to varying degrees of severity. In my opinion, it is a "design flaw", or more likely a "design oversight". There is something about this SUV platform that is significantly "worse" than others.

 

As I've pointed out before, the phenomenon of "boom" and "drone" is extremely common in vehicles. There are literally hundreds of technical papers addressing it in the auto industry. But, most vehicles it is under control, and hence not noticeable or not annoying. Since dealing with this issue, I have paid attention to all vehicles I drive and every SUV booms when it goes over a pothole or such. But, the sustained booming which becomes the buffeting doesn't happen to them - only the new GM full size. So, there is something about this platform that is either too stiff, or too flexible, or a resonance they missed...or something. Lately, it seems more like a shuddering or fluttering that ends up being the buffeting. And it does seem to come and go, almost like a phasing issue between components.

 

Bottom line, I have zero expectation GM will "solve". This. They will throw some parts at it. New tires. Try to appease the customer until warranty expires. They will win on attrition alone. They will outlast all of us combined. And because this in not a safety related issue, they will invest absolutely minimal resources. In fact, I can almost guarantee that the corporate attitude to this is "fussy customers. There is nothing wrong with this vehicle". That has always been the GM corporate mentality and still is to this day.

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.

Edited by Zig10
Posted (edited)

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?

 

This sums up where we are with our XL as well...I can only stand to drive it for quick 10min trips. It's unbearable to drive any longer and if if the roof bow attempt and new wheels/tires don't make it acceptable the truck will be gone asap. I'm so disgusted with the whole experience and only wish I would have taken more time before purchasing. But then again, who would ever imagine dealing with buffeting and cabin pressure in 2015 vehicle, let alone $60K+ truck.

 

With 4 kids and current lifestyle, I really want to like the truck but given everything I keep hearing, it appears that we will be shopping for a replacement sooner than later.

 

Also, like a few others have noted, I have noticed within the last few weeks with colder temps that the buffeting/pressure has gotten worse.

Edited by ajs800
Posted

We need a thread with a head count on who had the problem and got it fixed and what fixed it or improved it. And who had no success and what they tried to fix

Why not throw a few sand bags on top? Take a drive. That will tell you........something.

Posted (edited)

Utility trailer road trip experience with my 2016 Yukon Denali

 

3 hour drive with a loaded (1000 lbs) utility trailer on country roads (64 mph) and interstates (75-80 mph). No buffeting or vibrations present. Very quiet. Unhooked the trailer at the place of business and drove without the trailer for another 2 hours. Buffeting, vibrations with the sensation that the Denali was on very small rubble strips.

Back to hook up the trailer and loaded up for the 3 hour trip home, no buffeting or vibrations.

 

My 2016 Denali has never been (even after all the work to try to correct the issues) a luxury vehicle to take on long road trips. Around town is just okay (still get the low speed booming) but out of town - forget it. Unless you're pulling a loaded trailer!!!

 

utility trailer unloaded - bad rhythmic harmonic vibrations

utility trailer loaded - perfect

 

snowmobile trailer unloaded - bad rhythmic harmonic vibrations

snowmobile trailer loaded with 1 sled - noticeable rhythmic vibrations

snowmobile trailer loaded with 2 sleds - perfect

 

28 foot V-nose construction trailer unloaded - perfect

28 foot V-nose construction trailer loaded - perfect

 

Airflow over the Denali definitely could also be a factor. I did notice a difference when I installed a bug deflector on the hood. Not a big difference but better.

Edited by 16Denaliguy
Posted

Utility trailer road trip experience with my 2016 Yukon Denali

 

3 hour drive with a loaded (1000 lbs) utility trailer on country roads (64 mph) and interstates (75-80 mph). No buffeting or vibrations present. Very quiet. Unhooked the trailer at the place of business and drove without the trailer for another 2 hours. Buffeting, vibrations with the sensation that the Denali was on very small rubble strips.

Back to hook up the trailer and loaded up for the 3 hour trip home, no buffeting or vibrations.

 

My 2016 Denali has never (even after all the work to try to correct the issues) a luxury vehicle to take on long road trips. Around town is just okay (still get the low speed booming) but out of town - forget it. Unless you're pulling a loaded trailer!!!

 

utility trailer unloaded - bad rhythmic harmonic vibrations

utility trailer loaded - perfect

 

snowmobile trailer unloaded - bad rhythmic harmonic vibrations

snowmobile trailer loaded with 1 sled - noticeable rhythmic vibrations

snowmobile trailer loaded with 2 sleds - perfect

 

28 foot V-nose construction trailer unloaded - perfect

28 foot V-nose construction trailer loaded - perfect

 

Airflow over the Denali definitely could also be a factor. I did notice a difference when I installed a bug deflector on the hood. Not a big difference but better.

Somebody in the vibrating truck thread just made the same observation as you.

 

http://www.gm-trucks.com/forums/index.php?/topic/153186-Shake-or-Vibration-Issues

 

If fact, I think this was mentioned before in either of these long running threads.

 

This clue should help an engineer isolated it, no? Please!

Posted

Somebody in the vibrating truck thread just made the same observation as you.

 

http://www.gm-trucks.com/forums/index.php?/topic/153186-Shake-or-Vibration-Issues

 

If fact, I think this was mentioned before in either of these long running threads.

 

This clue should help an engineer isolated it, no? Please!

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...

Posted

My dealer is replacing my vehicle. I had the XL but wondering if the non-XL will work just as well for my travel needs. Other than length and the 3rd row not being as comfortable are there any other differences?

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