Road/tire noise.

[4wheelpilot]

This is the information I've shared elsewhere for general car support:

2018 Kia Stinger GT1 AWD

So far I've done the following:

• Road Force Balance the original OEM Wheels (Bridgestone Potenza RE97AS-02, 225/45-R18
• Purchased new tires and have all Road Force balanced on install. (Michelin Pilot Sport 3+ A/S, 225/45-R18)

Characteristics:

• Vibration has an audible component - it can usually be heard - sometimes more than it can be felt
• This has two components. For the very first drive of most mornings it creates almost a resonant "hum" that I can "feel" in my ears. This never lasts long and may be unrelated. Otherwise it is just a sound that seems in sync with the vibration frequency
• With the Michelin noise characteristics, the once per tire revolution sound component seems slightly more pronounced. Unsure if this is an issue with the new tires or a result of the general road noise level going down with the Michelins (so that other noises are more regularly heard)
• Vibration is usually felt in multiple parts of the car, but more commonly the seat/body
• The issue is 100% related to the frequency/rpm of the wheels. I have used a vibration monitoring app on a couple of occasions and run FFTs on the results to show that the primary spikes are at the First and Second order harmonics for the wheel rotation speed.
• I haven't done many tests, but the Second order harmonic is often similar in amplitude to the first and is occasionally larger.
• Vibration is speed dependent to an extent. It can be felt most strongly at 45mph and again at 60+mph. In between and before are much less noticeable.
• Vibration comes and goes (unrelated to speed)
• Usually worse in the morning/first drive of the day (had assumed this would implicate tires)
• Can go away for stretches and have a pretty smooth ride - but then come back

Of note: the Vibration is really quite low in intensity. I would almost suggest that many people wouldn't be bothered by it. The only reason it bothers me/that I notice is that A) I have never had a car do this before, B) It comes and goes so I am unable to just "get used to it"/"have it fade away into the background", and C)Every review touted how this car was more "Grand Touring" than "Sport", but issues like this eat into that.

I'm frustrated or you.
Spending money hoping for improvement and not getting it is tough.
I also have a GT1 and haven't noticed anything "excessive" regarding vibrations nor noise.
What may be helpful is test driving other GT1s (at dealership or another owner's GT1 if you have somebody nearby).
This way you can get a better idea if it's just your GT1 or all GT1s.
I'm switching out to Michelin PS A/s 3+ tomorrow for better handling.

 

[4wheelpilot]

So I also got the Michelins and I do think the handling is markedly improved! Road noise also better but certainly not excellent. For now I’m ok with how it drives.

[

Did you change tires because of problems with the Potenzas or to improve handling?

 

[patriotsfan82]

Sorry to hear about your issues. I have an awd and dont notice wierd vibrations. only if I'm on a crappy roads that aren't smooth or paved poorly but not to the extent something seems wrong or unbearably annoying.
Have you tried a test like e.g. use stinger vs another car on exact same roads going similar speeds and note areas where u feel the stinger vibrates wierd. Then see if the test car makes some noise or vibes st thise locations. Only suggesting coz sometimes a road looks smooth from the car but can be pretty rough when driven over. Hope you can get this fixed / figured out. Best of luck

I'm frustrated or you.
Spending money hoping for improvement and not getting it is tough.
I also have a GT1 and haven't noticed anything "excessive" regarding vibrations nor noise.
What may be helpful is test driving other GT1s (at dealership or another owner's GT1 if you have somebody nearby).
This way you can get a better idea if it's just your GT1 or all GT1s.
I'm switching out to Michelin PS A/s 3+ tomorrow for better handling.

Driving another Stinger is on my to-do list. Haven't been any good candidates at my local dealer and I haven't broached the topic with them yet. May try to track down another owner in the area.

As for other things I've attempted to "debug", roads are high on the list. For one, the issue appears on the same commute I've traveled for the last 7 years or so. Operated 3 other different cars in that time and never had a similar issue. Additionally, in my attempts to figure this stupid thing out, I've gone out of my way to drive the routes at different times of day, different temperatures, with the car warmed up, with it cold, etc. Pretty confident its not the roads.

Also, yes - I have definitely put an unhealthy amount of behavior into tracking this issue down for how relatively minor it is. To expand on what I said earlier - the issue (when it occurs) probably wouldn't compromise the ride "comfort" for most folks. Its primarily the annoyance factor that keeps me fixated on it. Like a rattle - it doesn't hamper the car in any real meaningful way, but its mighty annoying.

 

[SnazZ]

@patriotsfan82 I'm right there with you. I think I have the exact same issue as you with my Stinger. We drop this kind of dough on a nice car and we're left with stuff like this to figure out. I'm annoyed to the point where I want to do something about it, but I also don't want to start throwing money at the problem for potentially no benefit. My main complaints are the odd vibration that you can hear more than feel that starts at 40mph and is horrid at 45. It goes away mostly until you hit about 60 then sounds like it does at 45 again at 65. Vibration stuff aside, the tires are just plain noisy at all speed. I was thinking about asking the dealership that sold me the car what they'd be willing to do, but I think that would end in more frustration.

 

[patriotsfan82]

@patriotsfan82 I'm right there with you. I think I have the exact same issue as you with my Stinger. We drop this kind of dough on a nice car and we're left with stuff like this to figure out. I'm annoyed to the point where I want to do something about it, but I also don't want to start throwing money at the problem for potentially no benefit. My main complaints are the odd vibration that you can hear more than feel that starts at 40mph and is horrid at 45. It goes away mostly until you hit about 60 then sounds like it does at 45 again at 65. Vibration stuff aside, the tires are just plain noisy at all speed. I was thinking about asking the dealership that sold me the car what they'd be willing to do, but I think that would end in more frustration.

Your explanation is about as good as I can put it. With my new tires especially, the audible component is the most noticeable part and it occurs at the same speeds you mentioned. I’m admittedly really picky with my vehicles but it’s also, like you said, a lot of dough. It would be nice if vehicle manufacturers had some kind of brand wide customer service that would make sure issues like this were dealt with - but that simply isn’t the case in the industry. Dealerships are responsible for the customer service side of the equation and you are simply at the mercy of your local owner.

I’m a sucke for good customer service and have literally never received it from a car dealership. Makes me furious.

 

[Joseph Spiegel]

This is the information I've shared elsewhere for general car support:

2018 Kia Stinger GT1 AWD

So far I've done the following:

• Road Force Balance the original OEM Wheels (Bridgestone Potenza RE97AS-02, 225/45-R18
• Purchased new tires and have all Road Force balanced on install. (Michelin Pilot Sport 3+ A/S, 225/45-R18)

Characteristics:

• Vibration has an audible component - it can usually be heard - sometimes more than it can be felt
• This has two components. For the very first drive of most mornings it creates almost a resonant "hum" that I can "feel" in my ears. This never lasts long and may be unrelated. Otherwise it is just a sound that seems in sync with the vibration frequency
• With the Michelin noise characteristics, the once per tire revolution sound component seems slightly more pronounced. Unsure if this is an issue with the new tires or a result of the general road noise level going down with the Michelins (so that other noises are more regularly heard)
• Vibration is usually felt in multiple parts of the car, but more commonly the seat/body
• The issue is 100% related to the frequency/rpm of the wheels. I have used a vibration monitoring app on a couple of occasions and run FFTs on the results to show that the primary spikes are at the First and Second order harmonics for the wheel rotation speed.
• I haven't done many tests, but the Second order harmonic is often similar in amplitude to the first and is occasionally larger.
• Vibration is speed dependent to an extent. It can be felt most strongly at 45mph and again at 60+mph. In between and before are much less noticeable.
• Vibration comes and goes (unrelated to speed)
• Usually worse in the morning/first drive of the day (had assumed this would implicate tires)
• Can go away for stretches and have a pretty smooth ride - but then come back

Of note: the Vibration is really quite low in intensity. I would almost suggest that many people wouldn't be bothered by it. The only reason it bothers me/that I notice is that A) I have never had a car do this before, B) It comes and goes so I am unable to just "get used to it"/"have it fade away into the background", and C)Every review touted how this car was more "Grand Touring" than "Sport", but issues like this eat into that.

Forgive me if this was asked earlier. Have you gone back to the dealer and test driven similar variants to yours. Can you duplicate the feeling/sounds on another car?

 

[patriotsfan82]

Forgive me if this was asked earlier. Have you gone back to the dealer and test driven similar variants to yours. Can you duplicate the feeling/sounds on another car?

My local dealer hasn’t had a GT model in recently that they would let me test drive - only base models and premiums. At this point I think they have had enough of me pestering them for a fix that I’m not sure they would let me drive a GT anyways. Holding out hope to meet a local GT owner that will let me drive theirs once or twice.

 

[MerlintheMad]

My local dealer hasn’t had a GT model in recently that they would let me test drive - only base models and premiums. At this point I think they have had enough of me pestering them for a fix that I’m not sure they would let me drive a GT anyways. Holding out hope to meet a local GT owner that will let me drive theirs once or twice.

Heh! Good luck with that! I haven't even seen another Stinger in private hands (outside a car sales place). And if you wanted to test road noise and vibration with my car (assuming we knew each other and were within striking distance), I'd have to do the driving. You could tell the differences you want to test for as easily in the passenger seat as being the driver. If that wouldn't satisfy, you'd have to just wait until you see another Stinger owner. That could take a while.

Vis-a-vis tires and road noise. I just completed a road trip of c. 2,285 miles. And if there was one thing I noticed it was different surface dynamics. Even on the same road, the sounds and vibrational differences could be extreme. Yesterday I noticed one section in Oregon that was so shrill it was like my car had turned into a banshee. Kia can make a car as sound proof as possible and such a road surface will defeat all efforts to produce quiet. I have 19" Michelins on my GT1. And other than wishing that my car was even quieter, there is nothing unsatisfying about the cabin quietude almost all the time.

 

[patriotsfan82]

Heh! Good luck with that! I haven't even seen another Stinger in private hands (outside a car sales place). And if you wanted to test road noise and vibration with my car (assuming we knew each other and were within striking distance), I'd have to do the driving. You could tell the differences you want to test for as easily in the passenger seat as being the driver. If that wouldn't satisfy, you'd have to just wait until you see another Stinger owner. That could take a while.

Vis-a-vis tires and road noise. I just completed a road trip of c. 2,285 miles. And if there was one thing I noticed it was different surface dynamics. Even on the same road, the sounds and vibrational differences could be extreme. Yesterday I noticed one section in Oregon that was so shrill it was like my car had turned into a banshee. Kia can make a car as sound proof as possible and such a road surface will defeat all efforts to produce quiet. I have 19" Michelins on my GT1. And other than wishing that my car was even quieter, there is nothing unsatisfying about the cabin quietude almost all the time.

That’s all I would be looking to do - tag along for a quick drive in a fellow Stinger owners ride.

And in the end I likely am being picky about the issue - it’s just that this issue produces a more annoying cabin environment than any other car I’ve owned/driven in the last 8 years - Ford Fiesta, Ford Focus, Ford Focus ST, Subaru WRX, Civic Si, Subaru Crosstrek. And this car is by far the most “cough” premium.

It’s a Kia with a nice interior, decent wheelbase, and big engine. My particular one does not meet my definition of premium at least.

 

[MerlintheMad]

It’s a Kia with a nice interior, decent wheelbase, and big engine. My particular one does not meet my definition of premium at least.

They touted the efforts to make it a quiet car. I think that the car design itself is quiet. But they screwed up choosing which all-weather tires to put on it. It is possible that your individual car has some issue that does not bother Stingers as a group. But that's what you are trying to determine. I hope that you do, sooner rather than later (if it isn't already too late for that to be said).

 

[patriotsfan82]

They touted the efforts to make it a quiet car. I think that the car design itself is quiet. But they screwed up choosing which all-weather tires to put on it. It is possible that your individual car has some issue that does not bother Stingers as a group. But that's what you are trying to determine. I hope that you do, sooner rather than later (if it isn't already too late for that to be said).

My base assumption is that I have an outlier or simply have an aversion to this exact issue when most of the population doesn’t. I don’t think it speaks at all to the overall quality of the model even though I have kind of said exactly that several times . Just frustration.

Appreciate the inputs

 

[phxgt]

They touted the efforts to make it a quiet car. I think that the car design itself is quiet. But they screwed up choosing which all-weather tires to put on it. It is possible that your individual car has some issue that does not bother Stingers as a group. But that's what you are trying to determine. I hope that you do, sooner rather than later (if it isn't already too late for that to be said).

I don't know oi this is the same issue I'm having but there are times I would swear a window is slightly open or a door is a bit ajar. Or of itsi because I have not driven a hatchback for a long time. But there does seem to be excessive road noise at times.

 

[MerlintheMad]

It's probably the road surface more than anything else. But that doesn't explain everything.

 

[SnazZ]

I've decided to take my Stinger in tomorrow morning to a nearby place that does Road Force balancing and ask them to diagnose the vibration. Hopefully they are in agreement that a road force balance should take care of the vibration issue and otherwise provide a diagnosis of the root cause. If the issue isn't resolved by a RFB, I'll have their diagnosis documented to take to the Kia dealer and get the issue fixed under warranty. Any wagers as to how this will turn out?

 

[MerlintheMad]

Any wagers as to how this will turn out?

I will risk nothing to guess that the test will produce nothing concrete. That is a pun, since concrete surfaces are the most annoying generally. That howler of a section three days ago in Oregon was hands down the loudest road noise I have ever heard. Thankfully it didn't last very long and was not repeated.

 

[Fergalis]

Yesterday I noticed one section in Oregon that was so shrill it was like my car had turned into a banshee. Kia can make a car as sound proof as possible and such a road surface will defeat all efforts to produce quiet. I have 19" Michelins on my GT1. And other than wishing that my car was even quieter, there is nothing unsatisfying about the cabin quietude almost all the time.

Kia skimped on sound insulation to help bring the car in as a value 'luxury' proposition. One early review between an Audi S5 and Stinger GT, measured the interior quietness substantially worse (average 7db) for the Stinger. A cursory look underneath the current car and inside under the mats, especially the rear section, confirms very little spent on panel damping and insulation. I'll bet the door cavities will be similarly devoid. Off the few urban motorways and expressways in New Zealand (which tend to be smooth 'black-top'), the vast majority of roads are paved with course granite chips embedded into a tar layer, and this fatiguingly 'roars' inside all low to mid-range Asian sourced cars (including Kia). A decent Lexus can muffle it well and so can a Stinger if equipt with a similar level of damping. I'm waiting for a 2019 Stinger to order, and when I take possession, it's off to a specialty auto audio shop to get the interior stripped and undamped surfaces fitted out with mass-loaded vinyl. I'm going to get them to photo document the job, and I'll share the pictures here.

 

[SnazZ]

So I had a local tire place Road Force Balance my Stinger's RE97AS-02's...see attached. I'm not sure how to read the results exactly, but it seems there were some minor adjustments made. My initial reaction is that the vibration issue is about 80% better. I can deal with that if it stays this way.

 

[Hojae84]

So I had a local tire place Road Force Balance my Stinger's RE97AS-02's...see attached. I'm not sure how to read the results exactly, but it seems there were some minor adjustments made. My initial reaction is that the vibration issue is about 80% better. I can deal with that if it stays this way.

Not sure but see if deflating tires help. I'm pretty sure 40 is inflated higher than recommended. Tire psi should be listed on your inside door jamb

 

[SnazZ]

Not sure but see if deflating tires help. I'm pretty sure 40 is inflated higher than recommended. Tire psi should be listed on your inside door jamb

Recommended pressures are 36 psi front, 39 psi rear for my 2.0T with 18" wheels. I'm not sure if the RFB report shows they put 40psi front and 37 psi rear or the other way around, but I will check the tires directly. If they're not the reverse of the recommended pressures, it's only 1 psi off and highly unlikely to make a difference with the now extremely subtle vibration.

 

[Waynerm002]

Curious to hear how this turns out. Hope this will help others with the vibration issue. If it does resolve your issue, I would contact KIA customer service and the dealer to let them know. Others can do the same so they can develop a TSB on this so dealers can resolve and KIA can make sure all Stingers are checked before being sold. On another note, I saw a video online which had Michelin PS 3 on 18” wheels, let’s hope they will ditch the Bridgestone RE 97s for something with great grip, comfort and lower noise level.