dbdave

About 150 or so posts back in this thread, I commented about wanting to purchase a new Suburban, but because of the problems mentioned here, I would wait. Well, the wait is over. I picked up a new 2018 in December. I test drove the vehicle specifically looking for the booming and buffeting problems around 40 and 70 mph. If I tried real hard I could pick up minimal buffeting and the booming was similar to what I've had in my 4 previous Suburbans. Neither were excessive enough for me not to purchase this vehicle. The vehicle has 20" wheels, 3.42 gear ratio, a sunroof, Continental all-season tires, the 5.3l V8. I have noticed that at about a steady 40 mph, the transmission is in a gear that allows the engine to be lugging while trying to maintain that speed, and you can sense some buffeting trying to happen. It almost sounds as if the exhaust is creating a drone at that rpm range under load. It doesn't seem to matter whether it's in 4cyl or 8cyl mode. By selecting the tow/haul mode, the lugging goes away because the transmission then shifts to a lower gear and the minimal buffeting stops. The same situation happens at about 70 mph and by switching to tow/haul mode, the lugging/buffeting goes away. It seems that 40 and 70 mph are the points where the transmission is near the shift point. I suspect some of the concerns with these vehicles result from the programming of the transmission shift points resulting in the transmission staying in too high of a gear for too long so they can claim better fuel mileage. I'm very happy with this vehicle and I'm glad I waited. I may have been lucky enough to find a good one and I hope it stays that way. When you're driving what amounts to an empty airplane fuselage on wheels down the road, noises will surely show up.

You left out the rest of my quote which is the most likely scenario. They aren't, at this point, reliably fixing this problem. Maybe because they don't know what's causing it or the fix is just too expensive to do a good-will fix or a recall. The solution will then be left to a new gen design for which they will have budget to design in a fix. Like many other design problems, this one will go away with the age of vehicle, ownership changes to those who don't mind or care about the problem, or the vehicles go out of service due to accidents, etc. Who knows? We'll see. Until then, I won't be buying this version.

Which makes it appear that Gm got both the airflow and the construction materials wrong on this version. I'm thinking it will take a new version of this vehicle to correct the problems, since it doesn't appear there is a reliable fix for any of them.

Maybe reading it would open your eyes a bit to the effects airflow has on a vehicle, which appears to be most of the buffeting in all vehicles.

I guess you need to read the article then?

They made them smaller than they used to be. Maybe folding them in or removing them is the wrong direction to make any difference. The go pro thing was done by someone already and it moved as was posted way early in this thread.

Been following this thread since the beginning, waiting for a hope of this problem being resolved. I need a new Suburban pretty soon! I just read an article about buffeting in the latest Car and Driver that made me think about this thread so I thought i'd just mention it. Their conclusion was that buffeting is caused by outside rear view mirror design. They gave no specific vehicles, just aero testing. Maybe it's related since the mirrors on these vehicles were made smaller in the latest version. Just adding more fuel to the fire.

I completed most of the 57 pages and think I didn't see anything on this air vent possibly being the cause of the buffeting. I don't know for sure that the new 2015 Suburbans, Tahoes, etc. have incorporated this technology for cabin venting, but if they do, I suspect this thing could be contributing to the problem. http://gmauthority.com/blog/2013/02/2014-corvette-c7-first-to-use-gm-developed-lightweight-smart-material/ It doesn't work as intended on the new Corvettes so there's a good possibility, if it's used in these vehicles, it's a failure, too. I would suspect the cabin pressure would be oscillating quite badly if this vent was opening and closing harmonically as the vehicle was traveling down the road. I offer this as a thought just in case no one else has looked in this area. I'm watching here because I will be replacing my current Suburban in the near future but not until some word of the fix for this problem.