sbmike

As you can see, I'm new to the forum but I did use the search function thingie and didn't find anyone with a similar issue.

As I stated in my intro, I have a 2016 Stingray and only have about 700 miles on it. I have been driving it mostly soft but have punched it a few times and taken it around corners faster than the posted speed limit but I've got a weird vibration I have never encountered in any other vehicle I've owned. Starting at around 60 mph to around 75, I'm getting what can best be described as a mild version of running across rumble strips. I get the staccato rumble, then smooth, then staccato, then smooth. Just to make sure it wasn't just me, I had a friend ride with me and he felt the same thing. I've tested it on many roads so it's definitely the car and not the road surface. It is a mild vibration and if the road surface is erratic enough you can't feel it, but on those parts of the road where it is smooth you can. The vibration is felt on the backs of my legs and on my butt, which I think means the issue is likely coming from the rear of the car, but who knows?

Any thoughts on what would cause something like this? I've had tires that were out of balance, but the vibration is constant with that. I've also had tires/wheels that were out of round but the vibrations again are constant and tend to get worse the faster you go. This one has me stumped. I took it in to the dealership and was told (surprise, surprise) they could not feel any vibration. But they told me that if I still feel it is an issue, I should bring it back in after it has 1000 miles on it to make sure the magnetic suspension and everything else has settled in properly. I figured before it goes in, I'd see if anyone on this forum has run into anything like this.

joemessman

How does it shift? Automatic or Manual? If an automatic, does it shift smoothly?

meyerweb

Definitely not normal.

The dealer tech probably drove it for a mile or less, didn't notice anything, and said NPF (no problem found).

When this happens, can you hear it as well as feel it? If so, have your friend record video (and audio) while it's happening so you can play it back for the dealer. Then ask for the tech or service writer to go for a drive with you, and drive it until it happens again.

sbmike

It's automatic and shifting is very smooth. No issues there.

sbmike

Nothing audible. Just the subtle rumbling in the seat of my pants. Definitely will ask for service manager to ride with me. Thanks.

DickieDoo

are you sure it's not going into 4 cylinder mode ? maybe you have a problem with 4 cylinder mode that makes it vibrate more? Just a thought... the other thing might be wheel bearings.

Pelee4me

Sounds like exactly what I just went through. I felt the rumble strip type vibration but it was only in V4 mode. Turned out to be a bad torque converter.

iclick

While driving back home from the dealer last February I noticed some very mild shaking as you describe on light acceleration at highway speeds, probably in 7th or 8th gear. It was apparent while varying the speed as per the break-in procedure, but not at lower speeds. It's a 2015 with A8.

After that ride of about 90 miles I recall noticing it for a few days thereafter but not since. The sensation reminded me of my old rear-drive cars that needed a U-joint replacement, but in this case it was very mild and a matter of feel with no associated noise. Could it have been flat-spot(s) in the tires that worked their way out after a matter of days? The car did sit at the dealer for about a month before purchase.

HANNY

could be as simple as tire balancing or a bad tire in general to something more intrusive like a driveshaft either the one in the tube or one of the rear axles. On an extreme unlikely part would be engine out of balance or a transmission that has an issue like tourque convertor or internal.
all of those things would and could feel about the same. if you have a spot where you can make it happen every time take the tech to that spot and show them. I would doubt its the 4 cylinder activation since cruising along under anything but low throttle it wont engage but its possible of course it could be engaging and its not suppose to be. wish you lived close by (im near Wichita ks,) and I would take a drive with you and could identify it pretty quik, a good tech would be able to do that as well.

Some simple testing to get us more info: In the short term double check your wheel lug nuts just to be sure one wheel isn't loose. Also, where the spot and speed its happening manually shift into a lower and higher gear and see if its still there, if it isn't then you might assume trans. also when its doing that issue see on the display if its doing the V4 mode. try it in track mode to I think v4 doesn't engage when in track mode (that might be wrong but it will give us and the dealer more info) just mess around with the shifting gear and see if it changes, if it doesn't then something might be out of balance like a driveshaft etc.. and hopefully not a trans issue.
AGAIN: if you have a spot where you can make it happen every time take the tech to that spot and show them, if he's any good at all he should have

My guess? really hard to say without being in the car but I might lean toward an axle shaft but that's just a guess based off your story. good luck and keep us updated. paul

HANNY

that does sound like a tire issue, those runflats are a pretty weird deal. the sidewall has got to be just stiff and I could see those things having balancing issues occasionally and a flat spot could of been there to that worked itself out,,,,,,,, good outcome for yaa kid

bob guzzy

Make sure the tires are warmed up and the air pressure is right, then if you still feel the rumble have the tires re-balanced.

Ask them to pay particular attention to the wheels you may have a bent wheel or two

Years ago, I went round and round with a car with bent wheels, they didn't find them until after 2 sets of tires and many balance's with many hours of looking.

Subsailor661

Had a similar issue on my 2016 Z06. Took it to the dealer today and was told that multiple tires were out of balance. Weather today was a little wet so I did not get to verify the fix. Will check and update when the rain stops.

carpe dm

Have them check it out. Good luck.

sbmike

Thanks for your and all the other responses. The vibration is there no matter what gear I'm in or what setting it's on (Tour, Sport, etc.). It happens when accelerating, decelerating, and coasting. As I've stated, the really weird thing about it is the rhythmic vibration rather than a consistent one. Hopefully it will be something that the dealer can diagnose quickly. I'll post again after I take it to the dealer in a couple of weeks.

Gymbow

Does it occur with the A8 in 'M' manual mode? That disables AFM V4 from engaging.

sbmike

I'll try that the next time I drive it. Thanks.

joemessman

I spoke to a mechanic friend of mine about this issue and he indicated that it is more than likely a wheel or tire that gets in a rhythm at that particular speed variance and sets off the vibration. Very frustrating I know, but it will get solved!

HANNY

that stinks that didn't catch it, one of the easiest things to check is lateral run out (which we always did especially if the wheel needed a lot of weight added to it). Pretty Simple, while the wheel is spinning on the balancer just hold something next to it like a straw or something plastic that wont scratch the wheel and watch the wheel while its spinning, pretty simple easy way to check lateral run out, should be checked on every wheel while you have it spinning on the balancer.

kevpull

Bent wheel... Had the same problem on my C5

sbmike

Unfortunately, the cold weather combined with the snowmageddon here in the DC-Balt area, the car has been lounging in the garage for over two weeks. I discovered first hand that driving when the temps are at or close to freezing do not make a good mix for those non-winter type tires so it's going to have to warm up a bit and the snow is going to have to go away (which probably will be a week or more) before I can get the car back out and back to the dealer. Who knew?