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So hear is the weird thing......this past weekend we got a pop up message on the console something like “caution steering assist is reduced drive with caution” And the AC quit working. Car drove fine except for the messagand no AC. Drove around Sunday with intention of taking car back into dealer Monday morning. We then realized the annoying Drone was gone!!!!!! Great except for no Ac and weird message...


Well...... Monday morning and message was gone and AC was working again and still no drone!!!!! So far...

Beginning to believe that this might be computer related. There was something about the Buick enclaves that had a cable that leaked signals across the wires and caused all sorts of weirdness. Maybe a loose connection or something.

Please let me know if you find anything as this is too weird.

Weird to us, maybe not to the programming in the ECU.



Drone sounds like it is engine exhaust noise when it is placed under heavy load......the noise is normal, although maybe not when at such a high level. "Load" is not only the weight of passenger load but the parasitic load of accessories on the engine itself, i.e. load of the high amperage alternator output when feeding the huge AGM battery, the electric motor on the steering rack (no power steering pump) and HVAC motors; and the A/C compressor.


Just a guess
That weird message related to reduced steering and inoperative A/C might be the ECU's effort to reduce mechanical loading on the engine itself which will indirectly affect engine noise at the resonance point.......sort of like the message: "battery low, start engine" you sometimes get when playing the radio with the engine off, even though there is still plenty of reserve in the battery. The caution regarding steering assist loss may be the ECU's effort to cut power to the steering motor and A/C clutch and HVAC motors to reduce engine loading. Might want to check the tightness of the connections on the battery and the crap load of fusible links coming off the battery. A loose connection could be placing an abnormally heavy draw on the alternator.
 

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I’ve got this issue in my new 2018 traverse high country. About 6500 miles. Exactly the same perameters as you’ve discussed and I was able to record it with iPhone. Have an appointment this Thursday to see what they will do... this is very load obnoxious sound.. I’d love to know what you all have found with your dealers?!
 

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Well after the day of no ac and weird messages the drone is back louder than ever. It also seems to be happening more often and at lower weights now.

Again this isn’t the sound of a motor working hard than normal. This is a rattle the family jewels kind of noise.

Headed back to dealership this morning and they can keep this thing until they fix it or give me a new one.
 

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Well after the day of no ac and weird messages the drone is back louder than ever. It also seems to be happening more often and at lower weights now.

Again this isn’t the sound of a motor working hard than normal. This is a rattle the family jewels kind of noise.

Headed back to dealership this morning and they can keep this thing until they fix it or give me a new one.

There is a normal resonance noise at that rpm, but it should be nowhere near the level of a jewel shaker. Somewhere, something is amplifying the noise to an abnormal level.



Certainly sounds like it is engine related and nopise ios being transferred most likely through the exhaust system....a noise that you can feel on the floorboard, way in excess of normal resonance noise, sounds more like an exhaust leak in the flexible coupling to the engine pipe vibrating off the chassis, or the cat converter heat shielding or a loose hangar or one of the pipes/ muffler touching the body amplifying the normal exhaust noise.



Effect of weight could have something to do with lowering a chassis component closer to or touching a part of the exhaust system transferring sound. If so it will be difficult to locate without first weighing down the chassis or flexing the exhaust system when looking for interference.
 

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My dealer couldn't replicate my noise and said to come back when it's occuring more often so that they can hear it in order to help fix it.

It's happened once since then, and it was in wet/damp weather...I wonder if weather impacts it as well...I have not yet taken it back again but will if it's something I can easily replicate for them.

No A/C issues yet here...
 

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Contacting Chevrolet

We just purchased a 2018 Traverse High Country with 10k miles on it this month. My wife just experienced this issue while the vehicle was fully loaded. She said it was so load it hurt their ears. I contacted the Chevy dealer and they had no clue.

I plan on reaching out to Chevrolet corporate to raise the issue. I would suggest everyone here do the same thing. Once I have contact info I will post an update back to this site.
 

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High Country Traverse Noise -> Contact Chevy (not dealer)

We just purchased a 2018 Traverse High Country with 10k miles on it this month. My wife just experienced this issue while the vehicle was fully loaded. She said it was so load it hurt their ears. I contacted the Chevy dealer and they had no clue.

I plan on reaching out to Chevrolet corporate to raise the issue. I would suggest everyone here do the same thing. Once I have contact info I will post an update back to this site.
 

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Has anyone changed out the Purge valve on a 2018 traverse, getting a code PO442 small Vac leak, having trouble finding the location of it and nobody has posted anything on the internet about it so I joined this site for some help
everything online is 2015 or older and on those its right on top of the engine.


thanks
 

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High Country Traverse Noise -> Contact Chevy (not dealer)

We just purchased a 2018 Traverse High Country with 10k miles on it this month. My wife just experienced this issue while the vehicle was fully loaded. She said it was so load it hurt their ears. I contacted the Chevy dealer and they had no clue.

I plan on reaching out to Chevrolet corporate to raise the issue. I would suggest everyone here do the same thing. Once I have contact info I will post an update back to this site.
 

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Thanks. Sounds like it's not an uncommon issue. The first couple of times it happened I thought a motorcycle was in my blindspot. I thought it might also be an issue with active noise cancellation, but then I finally got it to repeat consistently. Now, I'm not going to say I was necessarily going a legal speed when I was able to trigger it to happen but maybe I could shift down to 6th or 7th gear at lower speeds and test it out as well.


I'm not sure there's much that can be done about it, but any ideas?
I have the same issue with my 18 high country its and obnoxiously loud exhaust drone from pass engine side its random and comes and goes once a week but it is extremely loud and resonates through whole car. Here it is 2021 and no fix yet.
 

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I have the same issue with my 18 high country its and obnoxiously loud exhaust drone from pass engine side its random and comes and goes once a week but it is extremely loud and resonates through whole car. Here it is 2021 and no fix yet.
I had an issue with my transmission, they did a transmission software update and flush, I have not heard the noise since then, that was over a year ago. I am hoping that fixed it.
 

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Had the same issue with my 2018 3LT and never found a solution after taking it to the dealership on three different occasions and even recorded the sound from inside my car to play back for them. I traded into a 2021 RS back in April and have not had that problem with this one thankfully.
 

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Same issue here, 2018 Redline edition. Skip to the last paragraph for the short n' sweet summary, read on for some simplified techie background on this issue...

It's definitely an internal exhaust resonance, not a vibration noise between exhaust and anything else. Every engine (actually everything) has resonance points, called nodes. For clarification, the full term we're experiencing is called resonant frequency, and it is a natural frequency of vibration determined by the physical parameters of the vibrating object. These resonant frequencies occur all over the vehicle, hence all the dampening materials installed everywhere to isolate and change the resonant frequency points (nodes) to values outside of the normal operating environment, or to values that would provide a benefit (anyone remember "tuned port" fuel injection marketing?).

This loud droning noise that we hear is due to a resonant node of a baffle inside the exhaust (likely the muffler), and it occurs at a particular exhaust pulse wavelength which "vibrates" the baffle at it's natural frequency, which amplifies the normal exhaust sound exponentially to a point that we clearly notice a distinct change in volume/tone.

All that technical BS aside, for our vehicles the conditions under which this droning noise occurs tend to be around 2,000 rpm and with added weight to the vehicle. Gearing doesn't matter, I could reproduce this in low gears as well but generally the auto trans will shift into a higher gear so to reproduce you'd need to go into manual mode...I first noticed it when we took a family vacation trip, so 4 people, all our luggage & foodstuffs, plus a roof rack cargo container full of stuff. On the highway, with a slight incline grade, at about 65-70mph it would hit this point and drone on until I made a throttle adjustment. With the added weight and the slight road incline, the throttle position was such that the ECM/TCM (engine & trans computers) wouldn't call for an upshift into OD or a downshift for more torque. Under everyday driving conditions, i.e. not loaded down with extra cargo weight, I might hear it once in a blue moon.

Bottom line, there is nothing mechanically wrong, this noise is not a precursor to an impending breakdown. It is however a nuisance, especially on a long highway road trip with a weighted down vehicle and relatively flat road conditions... Solutions? A few come to mind, although some are just not reasonable...
  • As mentioned by @Thomcat, use the manual shift mode to change into a lower or higher gear.
  • Reduce the amount of weight in the vehicle (not always possible/reasonable).
  • Change exhaust components with aftermarket parts. This would be a needle in a haystack thing unless an aftermarket manufacturer were to confirm their components have different resonant frequency nodes.
  • Make sure your vehicle has the latest ECM/TCM firmware installed. Dealerships will do this free if vehicle is still under warranty. GM could easily fix this issue with firmware changes to shift points based on engine load (throttle position) to keep the engine/drivetrain out of this resonant frequency node. If they ever do fix this nuisance issue it will be via an ECM/TCM firmware update, so make sure you have the latest updates.

- I almost forgot this last solution, as mentioned by @No2rdame, turn the music up really loud to drown out the drone!
 

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I don't know if the resonant frequency is related to the exhaust pipe itself (i.e., vibration of the pipe) or if it's related to the exhaust flowing through a certain length of pipe (i.e., like blowing across various sizes of bottles).

If it's the former, you might be able to change the resonant frequency by strapping some weights to the exhaust pipes in several locations. Seems easy to do, relatively cheap, and it might just work.

If it's the latter, shortening or lengthening the exhaust pipe would change the frequency. This would be more difficult to do.
 
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