2015 YUKON NOISE IN CABIN

xspecmor · November 1, 2015

Kind of not tracking with your post. The only opening in the front of my truck that allows air to circulate is the honeycomb grill, no other opening and the truck does not buffet. There is no cutout unless you happen to have tow hooks

That was Gen 3, the opening in the bumper was for exposed tow hooks and an opening for circular fog lights, don't think the engineers intended those openings for air flow.

Hey Zip, while driving I notice the previous generation and the generation before all had openings in the front bumper in addition even the Ford Expedition and Navigator's have opening in the bumper. GM may not have been aware when making these vehicle a small design cue could cause such an issue.

Cl Houn · November 1, 2015

Just out of curiousity. Has anyone had them use the picoscope on their vehicle

yahtzee · November 1, 2015

My XL Denali has been in the shop since last Thursday, a week ago, for the vibration issues. This is the 3rd time it's been in the shop since I took delivery on 9/15/15. Went through the road force balancing dance and had two tires replaced. Fixed the vibration - temporarily. This past service visit has been frustrating as they didn't even drive the truck for the first 7 days it was there (I put an obd GPS device in it). They drove it Friday and initially said they didn't feel it. An hour later they claim to "have narrowed it down to the driveline." He said they were going to put a picoscope on it and see what that shows. Rhetorically, I asked him what the picoscope measured. He paused, put me on hold and clearly asked someone and came back on to tell me that it's a tool to measure vibration. Serious question - should a service manager know what a picoscope is?

He also told me that the smaller non-XL's were less prone to the vibration and buffeting and they'd entertain moving me to one of those if my truck can't be fixed. I'd actually consider that but only if I know for a fact that it doesn't have either issue.

Are there ANY trucks that DONT have these issues? Is it possible to get a truck that is as expected.

The Zip · November 1, 2015

...while driving I notice the previous generation and the generation before all had openings in the front bumper in addition even the Ford Expedition and Navigator's have opening in the bumper. GM may not have been aware when making these vehicle a small design cue could cause such an issue.

Maybe I'm not understanding what you mean by openings, but went outside and looked before I made that post, no vents at least on the Chevys. No matter, air vents are designed to cool an engine or release heat from the engine bay, if enough air got past the block I don't think it would result in buffeting in the cabin. But I won't discount it cause at this point all customers and dealers are just guessing. However, I don't believe the manufacturer is completely clueless of what's going on, I think they are hoping a bandaid will work until the Gen 5 hits the street. A bandaid will not work, if there is nothing wrong with the part they are replacing by using the exact same part, the result shouldn't change anything.

The Zip · November 1, 2015

He also told me that the smaller non-XL's were less prone to the vibration and buffeting and they'd entertain moving me to one of those if my truck can't be fixed. I'd actually consider that but only if I know for a fact that it doesn't have either issue.

Are there ANY trucks that DONT have these issues? Is it possible to get a truck that is as expected.

Being on the thread since page 1 and reading every page, I have also come to the same conclusion as your dealer on the standard size being "less" prone to the issues. I made a post on here somewhere that talked about it.

To answer your last question, yes. If you were near California Central Coast I would take you for a spin, my truck doesn't have any issues associated with this thread (buffeting, pressure, shaking, vibration). But I do believe all these trucks are in theory the same, it's just some things (length, interior volume, tire, wheels, engine/body mounting points, etc) that determine whether a customer experience the issue.

The Zip · November 1, 2015

Has anyone had them use the picoscope on their vehicle

He said they were going to put a picoscope on it and see what that shows. Rhetorically, I asked him what the picoscope measured.

As a customer, don't need a picoscope to tell me about a vibration. Ok, the dealer determine there is a vibration, what's next. Still don't know the cause to come with a solution to stop it?

The Zip · November 1, 2015

Went through the road force balancing dance and had two tires replaced. Fixed the vibration - temporarily.

This is exactly what happens when you replace two tires with the same tires, a temporary fix. To eliminate the tires, you need to replace them with a different suppliers tires. Then if it continues to happen, you have to replace the wheel with a different manufacturers wheel. Once you do that you can eliminate the tire and wheel causing the vibration. But to replace them (if not a defect) with the same tire, expect to remain at square 1.

The Zip · November 1, 2015

...they claim to "have narrowed it down to the driveline."

There are a lot of components in the driveline. The dealer should have found faulty parts, mating points off, parts not torqued to specs prior to making the claim of narrowing the issue to the driveline. If not, what led them to the driveline?

Edited November 1, 2015 by The Zip

Anon2015 · November 1, 2015

The fact you have a vibration is one matter. Determining the source, or fault, which causes the vibration is one of the many diagnostic functions of a picoscope.

Cl Houn · November 1, 2015

As a customer, don't need a picoscope to tell me about a vibration. Ok, the dealer determine there is a vibration, what's next. Still don't know the cause to come with a solution to stop it?

They use the picoscope to narrow down and locate the cause of the vibration. Might be the first time your dealer used this since they probably never had to deal with this before so they might be coached in the process. I think someone ended up having the driveshaft replaced and parts in the rear end replaced and adjusted to a different spec internally (rearend) which solved the problem

16Denaliguy · November 1, 2015

Shorty's also have the same problem. 4 in our area have the same issues, all documented. (1 - 2015)(1 - 2015i) (2 - 2016)

ajs800 · November 2, 2015

Given what was recently posted on the facebook page (someone claims to have a video showing roof flexion when the buffeting occurs with their suburban) stating the sheet metal is too thin and needs additional support, I decided to do a quick little experiment.

I loaded two pieces of luggage (approx 35-40lbs ea) and positioned them between each cross rail and strapped them directly on the roof in an attempt to limit the amount of roof deflection. I then picked a newly paved stretch of road and hit continuous speeds of 30-55mph...The buffeting was still present but it was greatly reduced and the overall sound/feel was very different which tells me the roof plays a big part in the problem. However, I am not sure if it's the direct cause. As it has been mentioned many times in this thread, the suspension and driveline vibrations may be the culprit and the cabin is essentially one big tin can enhancing noises/vibrations that resonate thus creating the buffeting. Who knows? I may attempt this again after I have the dealer swap out the 22s with factory 20" wheels to see if there's any change as the 22s definitely do not help the issue.

My dealer is telling me that they will have a GM engineer onsite this week (for another reason) and would like to have me drop the truck off and have him drive /inspect. I've told the dealer as well as the GM Sr. adviser that I don't want to have the TSBs done as they have yet to prove it fixes anything. Given what everyone else has experienced with GM, I am not expecting much, if anything, but it's worth a try.

I drove a 15i subrban ltz (sunroof, 20", no cross rails) with approx 35k miles on it and I noticed the buffeting to some degree but it was hardly noticeable compared to my yukon. ...such a mystery...

never thought I'd have to do something like this or even deal with such an issue in 2015...I can go drive a new very raw hollow base delivery van and not experience such issues.

Edited November 2, 2015 by ajs800

Cl Houn · November 2, 2015

I think it's safe to say that no one in this thread has had the dealer inspect with the picoscope we need a thread with the owners who have had the dealer inspect with the picoscope

16Denaliguy · November 2, 2015

I think it's safe to say that no one in this thread has had the dealer inspect with the picoscope we need a thread with the owners who have had the dealer inspect with the picoscope

The picoscope was used quite extensively on my Denali. Watched the GM engineer take it out of his vehicle and put a laptop and the pico in mine.