Just got my car, vibration/moaning on the highway

[yettavr6]

Well i finally picked up my car last night and while driving it home today i noticed a pretty bad vibration at around 80mph. I feel the vibration in the floor, and can hear it slightly. Think of driving on a rumble strip but not quite as violent. The steering and the brakes are smooth, this is coming from the drivetrain somewhere. It gets worse when you give it more gas and decreases significantly when you let off the gas and goes away completely when you depress the clutch. It pulsates in and out with about 1-1.5 seconds in between. I'm pretty knowledgeable about cars, and all i can say is i know its not the tires. I would have to guess a faulty motor mount or something screwy with the quattro, but wanted to see what you guys think? The car only has 3500 miles on it now, so obviously i'll be taking it to the dealer, but i'm sure they'll try passing it off as normal. Other than that I LOVE the car. I averaged 29.3mpg driving all highway 9 hours (!!!!) home. I actually think the Bose stereo sounds very good and overall just love the car. Chip will definately will be my first mod as the car feels pretty underpowered. I had driven one with more miles before i bought this one and it was definately faster so maybe it just needs to break in some more. Anyway if anyone has any thoughts on the vibration i would love to hear it.

P.S.
Last night in the hotel parking lot (i stayed over night in michigan) I did the basic vagcom mods, and put in yellow fogs as soon as i got home

[muffinman]

hits probably tire mount/balance issue - have a tire shop check .. And welcome

[yettavr6]

Nah i know its not the tires because its more dependent on the engine load then on the speed. If i downshift into 5th at the same speed it will go away. It also fades in and out very slowly, and it no relation to the speed of the car.

[Alkemix]

clutch? i would hope that it's still under warranty.

[yettavr6]

Hmm, that would be quite a shock but i guess thats a possibility. Whatever it is causes the gas pedal to buzz with the same rhythm. It almost numbs my foot.

[gyroscope]

I've got the same issue. Only does it in 5th ot 6th gear at speeds greater than 55 mph. I know that we have the same issue after you described "rumble strips". Thats exactly what it feels and sounds like. To my trained ears it sounds like it's coming from the rear differential somewhere. I don't drive my car much, only 11k on her right now, but once I do some heavy driving (300 miles or more) the sound and vibration comes back. If I let the car sit for a while it seems fine with no noise.

[Turn10]

did you check for dragging parts under the car? if not that then i would say something to do with alignment especially since you bought the car used...

[yettavr6]

Very strange. I was doing a 560 mile trip with only one small stop, but i didn't notice if it was doing it in the beginning. I wonder if maybe the diff fluid is either low or overfilled. Maybe a different type of oil would help it too. What weight oil do these things have in the diffs anyway? I actually hope it does it when it's cold too so they dealer can easily reproduce it. Its very discomforting in a car thats basically brand new. Have you taken yours to the dealers to see what they say it is?

[gyroscope]

Very strange. I was doing a 560 mile trip with only one small stop, but i didn't notice if it was doing it in the beginning. I wonder if maybe the diff fluid is either low or overfilled. Maybe a different type of oil would help it too. What weight oil do these things have in the diffs anyway? I actually hope it does it when it's cold too so they dealer can easily reproduce it. Its very discomforting in a car thats basically brand new. Have you taken yours to the dealers to see what they say it is?

The dealer changed my oil at 10k, and did all the neccessary checks, and top offs. It hasn't done it since, but like I said I barely drive it.

I did however notice that on my mothers Honda CRV, it was doing a similar type of vibrating and noise from the same area,. When she got it serviced they changed the differential fluid and the problem was solved. Not really sure what what Audi reccomends sofar as servicing the rear diff fluid. Has anyone changed theirs?

[yettavr6]

I have the tool to remove the drain plug so i may just try to change it myself with some redline and see what happens

[elwigglero]

Take it to an alignment shop and see if they can diagnose it. If you're in qtown, just take a quick trip up to Knopf Audi, if you're under warranty, they'll prob throw it on the lift for free.

[yettavr6]

I just made an appt at Don Rosen imports cuz its like 5 minutes from my work. I think gyroscope is on the right track with the differential. It really doesn't feel like its coming from the wheels or tires.

[drexplode]

I am the seller of this car, and I can say I never noticed a vibration except when i had the apikol snub installed. After about 2-3 days of having the apikol snub installed and trying to adjust it each day I gave up and re-installed the stock snub and lined up the nuts to the original position.

Most of my commute for the past 3-4 weeks has been around town, with very minimal highway/expressway travel.

I hope that yettavr6 is not ruined by this experience. I do apologize for the inconvenience...really.

FYI ...all wheels/tires were recently rotated (by me), torqued in a star pattern and to 90 ft-lbs.

I am definitely interested to hear the root cause of the problem. Maybe it is the stock snub placement? Even upto 60MPH I never noticed a single vibration...

[yettavr6]

Hey Greg! No, i am not upset at the experience at all. I still love the car and feel like i got a great deal, and got exactly what i was looking for . I keep going over to the window at work to look at it LOL. Anyway, I called the dealer and made an appt to get my state inspection and have them check it out. I would check out the snub mount myself but i dont really know what i'm looking at. Anyway, i'm sure its probably either that or something with the differential, hopefully that a fluid change will take care of. Although i have read some reports of people having premature clutch failure on these cars, I highly doubt its the clutch because the clutch feels fine otherwise. Even if it was, i think Audi would be smart enough to replace it under warranty on a car with only 3500 miles. I know you didn't beat on the car, and even if you did the clutch would have to be faulty to only last that long.

And i also just want to kinda clarify my description of the vibration since everyone seems to be thinking of a tire vibration. This is the best way i can describe it: Image theres a cell phone vibrating on the floor, and you can feel it in your feet, on both the floor and the pedals, and very faintly hear it. Thats what it feels and sounds like. Its not shaking the steering wheel or anything, or even causing the car to feel uncomfortable. You just notice it after a while on the highway, and my friend and I were both like...."do you feel that?"

[AudiWxGuy]

I had a vibration on my car at speeds above 60 mph when I first got it last year. The car was brand new. I had no idea what it was. And neither did Audi at first. They tried balancing my tires, replacing the front tires with new ones and it did nothing. The tires I had on then were BF Goodrich Eagles ( I think ). Eventually, on the third visit, they decided to switch tire brands. They gave me Michelin. Since then, everything has been fine! No vibration. I love the car even more.

As far as the vibration, it was harmonic and the steering wheel did shake, so it was clearly something to do with the wheels, or something rotating that would give feedback into the steering system. IT goes worse, the faster I went.

I'm also semi-convinced it may have been more than the tires as they had the car for a long time (about a week) and the car ran smoother (engine wise) after i got it back.....

[drexplode]

Hey Josh,

Great, i'm glad you are still as excited as you were from day one. Hopefully that d-bag on the way home didnt ruin the hood at all.

Wow, premature clutch issues?? That is the first i have ever heard of it. No, I never beat on it at all. Followed the break-in period correctly, and probably reached close to redline about 2-3 times (after break-in of course). I never ever ever hold down the clutch during idle situations. I always rev match when down shifting, and never achieve RPMs >4k after cold start. That clutch should be brand spankin new.

Ive never been a huge fan of the conti2's. I was praying and hoping that Audi would install MPS direct from the factory but they didnt. Drop the tire pressure a few PSI and try it again? I remembered to fill-up to recommended tire pressure before you arrived so you would get optimal fuel economy and to verify pressure in all 4 corners.

Definitely keep me posted on the outcome.

-Greg

[KMHPaladin]

Vibration and moaning, eh? Sounds like your car is almost there. Keep at it.