The Zip

I can't see how that would work unless they were fabricated parts not to specs. Fabricating parts to specs in essence would mean a replacement part.

No issues so far, let me guess xspecmor's setup - standard size truck SLE/T, 18 inch wheels but no more than 20. No roof racks, no sunroof, premium ride suspension, 5.3 engine, six speed, 3.08 rear axle, second row bench, no under body splash guard, no trailering package

I didn't think the roof racks would factor in with changing the set-up, but if you were in an identical truck with no pressure, change out the wheels? If your dealer is working with you, tell them to pull a truck off the lot with 20 inch wheels, change them out, and see how that affects your set-up. Why not? The parts being replaced are not defective or broken. I don't see a fix by changing them with the same parts?

The gen 2 and 3 Chevy Fullsize SUVs did not come with ANC and did not have the buffeting and pressure. Then the new gen 4 comes along with higher and thinner metal panels, more hp, and performance car suspension. Some of which I believe allows for more cabin noise and pressure. GM knows about this from the onset and what do they do, incorporate ANC to manage the cabin noise and pressure. I agree ANC is not the "cause", but I believe it was put in the new gen 4 trucks to be part of the "solution".

I have a thirty year old car in the in the garage, back in the eighties a 16 in wheel was about as big as they went on passenger vehicles and the tires were made with fabric cord. Today, a passenger vehicle has 22 in wheels as the norm and the tires have evolved with steel belts. Loose or bad belts can cause problems on an otherwise perfect looking tire, may account for what you describe as flatspotting.

If this is what you believe, why not spend the money and get the best shocks on the market?

Don't know if I am following this, the Tahoe LS, LT and the Yukon are the least expensive GM Fullsize SUVs. But if anyone of those trucks were taken to the dealer and asked what could they mod, the only thing that would be a problem would probably be the 6.2 and the Mag Ride, everything else is pretty much plug and play. Which would make these trucks the same. If that's the case all should have ANC. If not, based on your test the least expensive models should therefore have crazy road and wind noise. I have a LT, my RPO code says my truck came with ANC and I have no road or wind noise.

This has been tried on a couple other threads, lost steam and nobody did anything with the data once it was produced. My previous post identify most of that data. Also, most folks that are not having problems are not on this thread, I may be the only one.

I don't think ANC is out of tune or even if it can be tuned, but there are other components of ANC, GM may not have incorporated them into the system for the Fullsize SUVs. You are right about disabling ANC it makes it worse, even allowing more noise into the cabin. There are a few folks that did something with the mics, only one had a semi successful result with the pressure and buffeting. When you get your 2016, your age won't have anything to do with hearing the buffeting and it won't be fixed. All of the 4th generation GM fullsize SUVs have the issue, I think it's how well an individual truck set-up reacts with this new body and chassis. Whether or not it affects you will "probably" be dependent upon if your truck has the right combination of - wheels (18, 20, 22) / weight of wheels (chrome, aluminum) / length (standard, XL) / engine size (5.3, 6.2) / with or without ANC and how well it works / suspension (magnetic ride, premium ride) / sound dampening / sunroof / whether or not roof bows are attached / 4x4 / roof rails / skid plate.

Don't wait on yahtzee...

Shaking and vibration, yes GM should be able to fix this. But what is the logic believing GM can correct the buffeting issue, they have been working on it at least since July 2014 with no realistic end date of a fix. GM road forced balanced the tires, changed tires, changed wheels, reattached bows in roof, added more padding in the headliner, disabled ANC, changed shocks, and changed the driveshaft in an attempt to see if that impacts the buffeting, all to no avail. This would suggest GM acknowledges something went wrong and is attempting to throw everything on the wall to see what sticks. There are some on this forum that believes all of the GM fullsize SUVs are faulty and the reason that folks don’t hear the buffeting is because their ears are not sensitive enough. Personally speaking, GM knew about the issue, they just doesn't know how it went wrong to fix it. Folks like these trucks too much to stay away, some on this thread bought a truck three times after a GM buyback twice. Look at yourself, you probably read through half of this thread and still bought a truck. So, what motivation is there for GM to modify the design when there are record sales and repeat buyers? What I think, the trucks (Chevy/GMC/Cadillac) inherently produces escalating levels of noise and pressure. GM tried to mitigate it with incorporating Noise Cancellation in some form or fashion. The level of noise and pressure felt by the customer is probably based on an individual truck set-up (ie, bigger wheels, longer truck, different suspension, build date, quality control, etc, etc) in some combination versus differences in ear sensitivity. My ears are more sensitive than most so I would definitely notice buffeting and pressure. I don’t have a suggestion and identical models to mine does have the buffeting, but whatever the set-up combination of my truck, they got it right. Although to your points, I think the buffeting and pressure will be mitigated versus being fixed. Fixed would mean a new generation.

This is a catch 22. At this point, I think these TSBs are issued to pacify customers, not as a real fix to the many issues. But if you are fortunate enough to have your vehicle bought back by GM, the TSB work will probably be used by GM as a pre-condition to the buy-back. If you don't get the TSB work done, your expectation of GM customer service is probably correct. Prior to the TSBs being issued, 1 fella on this forum had his vehicle bought back by GM without any corrective work being done. It was due to his state having a 72 hr Lemon Law. The remaining half dozen or so folks with a buy-back had one or all of the TSBs completed.

Two people, this is a laugh-er. But to that point, some on this thread is not having a problem with all the issues (OP was about buffeting, the thread has evolved). Buffeting may stand alone or added with some variation of shaking, vibration, or pressure. The dealer attempting a fix all at the same time is not working. The issues may not completely go away as a whole, but a full redesign is not going to happen. It took Chevy 8 years to roll out the fourth generation Tahoe and GM spent hoops of dollars on factory equipment and inventory, not to mention Chevy is clearing a million dollars per 100 units. The only way GM comes out with a new design before 2020 (just long enough for your truck to go out of warranty) is if customers stop buying.

You and a couple of other "recent" followers on this thread are mentioning that you are primarily looking for size, if that is the case why not buy the previous generation (07-14) for size and trade it in when issues associated with this thread are sorted out? I have not heard of the same issues with the 07-14 generation. It’s sad that someone would even contemplate spending 80K on a vehicle knowing it has major customer complaint issues, and even worse, when someone test drive the vehicle then confirms the complaint. If you buy this truck, you'll need a lot of tolerance because luck won't help you at that point.

Kudos, way to go with being informed. I have not read if someone with a 2016 have commented on issues associated with this thread. The bad, if I was in your shoes I wouldn't buy a 2016 until the mid year model has hit the street, there should be enough time passed for issues to show-up. The good, GM has stop letting the dealers sink and issued PIT5318B and now should be addressing these issues at the factory versus the dealership. The logic of this is the 2016 models "may" not have the issues associated with the 2015 models.

Don't think owners and dealers are settled on the fact that the issue is primarily the rear end. Info on this thread suggest road testing from 18 - 22 tires sizes ended with similar results, although tire size may be a piece of the puzzle. I have 20's and don't experience the issue.

Taken the wrong way, the info you were posting would get more comments on a different thread, added info should at least be somewhat on point. Driving my truck since Mar 14 there is a laundry list of good things I could say about it, on another thread.

You know what Scurvey, that is good news about your truck and I could say the same about mine. But this thread is about folks that are experiencing vibration, shaking, pressure and buffeting with the GM fullsize SUV. Start another thread titled something like "Absolutely Love this Truck", your previous comments would read very well there. Been hanging around this thread since page one, just a constructive observation.

Are you experiencing any shaking or vibration?

Always worth posting. Looks like GM got most of the info in this document off this thread by finally compiling data based off customer input and dealers doing what they can to mitigate the issues. GM mentions V8 to V4 (AFM) transition, ANC, mics, amp, speakers, exhaust, powertrain, etc, issues talked about in length on this thread. Some suggestions on the document won't work, customers on this thread already tried them. This document also suggest this issue caught GM off guard, don't know how though. Just like a customer could identify these issues, a highly trained factory tech should have also noticed the issues. Afterall, they don't just make a truck and put it on the street without testing. However, there is one piece of new info for owners of the 5.3L engine (probably Chevy), engineers are working on improvements to the exhaust system, which may assist with improvements with the 6.2L engine.

baylorfan05 - If there is a defective or broken part, your warranty will cover it. When you take the truck in, be as specific as possible. For example, if the seat moves under hard braking, have the service writer annotate it like that on the paper for the service tech. If possible, have the service writer hop in the truck and advise him how to duplicate the issue while you are in the passenger seat. If you drop off the truck without any guidance, you may get a reply that they coudn't duplicate.

My truck doesn't experience anything associated with this thread.

When you say active ride control, are you referring to active noise cancellation? Also, wouldn't you say that the differences in the GM fullsize SUVs are basically lights, grilles, and interior. You know, general aesthetic stuff. You can also throw in a bigger engine on some. But for the most part the frame, body mounts, chassis are the same. How is it accounted for that some trucks are having this issue and some are not; maybe its the combination of a larger wheel size, larger engine size, larger vehicle size, and magnetic ride control. These things in combination as opposed to individually may be having a negative ride impact on the fullsize SUV line. Use my truck combination for example, I have 20" wheels, the 355 hp engine, the standard length truck, and Premium Ride suspension and my truck has been driving issue free since Mar 2014, why? Since most of the trucks with Magnetic Ride has the combination, an upgrade by softening the suspension may be a positive first step.

Reading through the Tech Bulletin posted by Cleanfreak, GM advertises a Magnetic Ride Suspension fix for builds prior to Feb 2015, however, the fix updates and reprograms the rear suspension but only replaces the front. No updates on the front won't change the performance of the component. Even if they happen to get the suspension spot-on, the Tech Bulletin specifically states it will not eliminate disturbances with the tire/wheel, propshaft, and rear axle. Technicians would have to refer to Tech Bulletin 1354 for those answers. So to sum it up the Shaking and Vibration piece, GM appears to have updated MRS REAR components for builds after Feb 2015. At this rate of progress (if you want to call it that), a new generation will be out before all this is sorted out. At least GM is beginning to acknowledge their fullsize SUV Quality Control Senior Managers need to be fired.

CI Houn - I have been commenting on this thread since page 1 and have read all 71 pages. According to data on this thread, two most frequent common denominators of the shaking, vibration, buffeting, and pressure (SVBP) in the GM fullsize SUVs was the extra length (EL) versus the standard length (SL) and the Magnetic Ride Suspension (MRS) versus the Premium Ride Suspension (PRS). But the most frequent common denominator, MRS, which is a standard feature in the Denali, Escalade, Tahoe and Suburban LTZs. There are problems with the SL with PRS, but data on this thread along with this Tech Bulletin suggest you will have more problems with SVBP with the EL and MRS.