I've had a problem with vibration on the highway ever since I bought the cart last July. I had a bad wheel bearing replaced, and new tires installed, and re-balanced as it didn't fix the problem. But I think they might've only re-balanced the fronts. Could imbalanced rears cause the steering wheel to vibrate at highway speeds? I can feel it in the seat and my legs and you can see and feel it in the steering wheel. What else can cause this?

67,xxx miles on the car., 2.7T quattro

Thanks!
Jeremy

i was always told that if you feel the vibration in your butt, and not the steering wheel... your rear tires are out of whack, and vise versa.

did it improve at all when they balanced the fronts?

Not really. I feel it in both places. Feet, seat, and wheel. I've been doing some more reading on it, and apparently it's a running theme!

I had the same problem.
1. Had the car realigned
2. Tires rebalanced
3. Found a rim that was bent on the rear.

Finally took care of the problem...smmmmooootthhhhh now.:D

Balance the rearsand check for a bent rim. If that dosen't fix the problem have someone do a loaded balance (tire under load against a drum) to see if the tires have a problem. Also make sure the tires are round... A good tire shop would do all these if there is a problem.

I had a Hyundai Sonata (V6 auto) with a balance probem. We worked on it for over two months on Saturdays. We rebalanced all the tires at least twice, changedtwo rims, put 4 new tires on the car -one at a time, and could not fix the problem. Since the guys did everything possible - they were a good shop and wanted to fix the problem - I finallyfigured it ws a car problem and decided to live with it. After 60,000 miles Iswitched to a different brand of tire and the bounce went away. Somewhat the same thing happened with our Dodge mini van - the origional tires were Bridgestones and they were never quite right. After we balanced them a few times we just gave up. At 50,0000 miles we put Yohohama TRZ's on it and the difference was fantastic.

well, all 4 of the wheels on the car had been curbed when I bought the car, and from doing a carfax, I know 2 or 3 of them had already been replaced, so the guy just had a habit of curbing wheels. However, none of them are "visibly" bent. It's worth a look, though... I'll def. go have the rears balanced, too.
NH_USA, where in NH are you located? What are some of the good mechanincs/shops you use?

Tires always have a low spot from the manufacturing process and if the process is poorly controlled, the low spots will give you a shake no matter what you do. Have a tire shop measure the run out of the tire and if it excedds 0.030", replace the tires. Michelin has the best reputation in this area.

Bob

This is probably one of the problems I see most on the forums. 99% one of your rims is bent. I had the same problem as you!

I too vote for a bent rim.

You could have a bend axle with a good curb check too. Always put your worst shaped rims in the rear you shouldfeel less vibration. So try swapping fronts with the rears!

ORIGINAL: jaymac

well, all 4 of the wheels on the car had been curbed when I bought the car, and from doing a carfax, I know 2 or 3 of them had already been replaced, so the guy just had a habit of curbing wheels. However, none of them are "visibly" bent. It's worth a look, though... I'll def. go have the rears balanced, too.
NH_USA, where in NH are you located? What are some of the good mechanincs/shops you use?



I live near the NH seacoast just north of Exeter and drive RT 495 to N Billerica for work each day. I don’t know a really good Audi mechanic so I end up doing most of the work myself. I get most of my parts from Chris at Force Five in Concord NH, a few on the internet, and some at AutoZone. When I don’t have time, I usually have J&R foreign car in Lowell do the Audi stuff and Price’s Sunnyside Garage in Newmarket NH do the American cars.

My son was an Audi-Porsche service writer at Dover Auto World but left after about a year because he didn’t like the way they did things. In all, we have owned or still own the following Audi’s -- 4000Q, 90Q, 200QT, A6, and A6 Avant Q along with a VW (the Audi wanta be) Jetta and Passat 1.7T. The best Audi investments I have made are manuals, and VagCom.

If you see a crazy old guy in a black A6 Avant in the left lane of RT 495 going 15 -20 MPH over the speed limit, it just might be me.

PS On Friday evenings during the summer, I usually get off at exit 52 to take the back road around Plastow so I can get to LEE-USA where I spend time in the tower making sure the drivers behave themselves.

I vote prop shaft as it only happens at speed, just a guess;)

"prop shaft"? What's that?

And NH_USA - Have you ever heard of Dan at Exeter Motor Works in Exeter? One of my clients swears by him. He works primarily on Audi's and Porsche's, and I've talked to him on the phone about my Tb, which he quoted me 7-800 to do. Seems like a reasonable price from what I read.

ORIGINAL: jaymac

"prop shaft"? What's that?

And NH_USA - Have you ever heard of Dan at Exeter Motor Works in Exeter? One of my clients swears by him. He works primarily on Audi's and Porsche's, and I've talked to him on the phone about my Tb, which he quoted me 7-800 to do. Seems like a reasonable price from what I read.


Prop shaft - Could be either a half shaft or drive shaft, but it makes me think that a CV joint or even a wheel bearing might cause vibration. Usually a bad CV joint will click when turning and a wheel bearing will make noise long before the vibration thing will happen.

I had some work done at Exeter Motor Works about 8 years ago and was not impressed. Maybe they are different now. I would be careful about 7-800 for a TB job. Make sure he is doing the Water pump, tensioners etc at the same time....

Do you recall if it was Dan at Exeter MOtor works? I know the person who referred me wasn't going there 8 years ago, so maybe it's a different guy?
I do get an occasional wheel shudder when I try to make a full-bore turn from a dead stop. Is that the same thing as a "click" you're talking about?

Also, where have you taken your cars for TB jobs? J&R's?

SUCCESS!!!! Everyone who voted "bent rim" was right, and everyone who said "check balance on all 4" and "tires out of round" was ALSO right!!!
I found a great, competent shop that found one badly bent rim, so they put on my full size spare. They said the Yoko's were junk and badly out of round, but I'll keep them for now since they're new. All 4 were also badly out of balance (eevn though I got them re-done several times!!).
So now all is well and it's like a BRAND NEW CAR on the highway!!!
can't tell you how happy I am :)

Happy to hear that you got it fixed.....Your Yoko's must have been trashed by the bent rim and other encounters with the curb. I can hardly wait until I wear out the Michelins on my A6 Avant and get new TRZ's.

I don't remember who was at Exeter Motor works, but I do know I was not impressed and did not go back.

As for TB. The two A6's had them done just before I got them.My son and I did the 4000, 90 Q, and 200QT.

What work did you have done at Exeter Motor? What was it that you were disappointed in?

As far as tires, which michelin's do you have now, and who makes the TRZ's?

The Michs are Pilot Exaltos - Inspit of what others have said about Michs, I have never been very impressed with them. The ride seems harsh and if I wanted something to really stick I would buy Pirellis.

I used to race Datsun's (Nissan) and Alfa Romeo's at places like Watkin's Glen and becamesensitive to what tires could do for handling. The Datsun handled best when it had Semprets on the rear and Pirellis on the front because of the pig loved to understear and they helped get a better balance. The Alpha was better balanced from the beginning so I used Pirellis all around.

I tried Michs on the race cars and it was a disaster. They are too hard for good grip and my current experience with the A6 Avant continues to confirm my opinion. I had SEAR's Michs on a VW bug years ago and they were just OK - good milage (hard), medium ride, and medium stick. I put BF Goodrich tires from Sam'son my other A6 (due to cost) and although they were not supergrippers they did a good job - smooth ride and realistic milage.


The TRZs are Yoko's. I recently replaced the OEM Brigdestones on our van with them and the difference was like night and day. In my opinion the Yoko's are fantastic and not very expensive. Iam looking forward towearing out the Michs and putting the TRZs on the Avant, but with the way things are going the Michs will probably last forever.

As for Exeter Motor Works -- I seem to think it had someting to do with a broken spark plug that I didn't have time to do myself because of travel for work. If I remember correctly they claimed they had to replace all the wires, plugs, cap and rotor to get the car running afterremoving the broken plug. It was strange because I hadput new one's on when I broke the plug. It also took them over a week to get to the car when then they had origionally told me that they could do it in two days. I was happy to get the car back and didn't have time to argue with them, so I decided to never return. I can understand problems but if I can't trust a shop, I don't go back.

Thanks for the info on the tires! As much as they said the Yoko's were junk, comapred to what they were before they re-balanced them and removed the bent wheel, I have no complaints at all. They said the ride is not as perfect as they'd like it to be, but I'm more than satisfied.

I actually have the same problem. it only occurs at speed, but often times when im braking at high speeds its more violent. Also sometimes when im breaking at slow speeds i can feel the car lurching and slowing rather than just a smooth break. (hopfully you get what im saying) I was told that could be a bent caliper... how could i check the calipers/bent rim, propshaft without taking it to a shop?

Most likely a rim or disc.

The rim can be checked by jacking up the car, positioning a fixed object next to the flange on the wheel, and rotating the wheel. If the distance between the fixed object and the rim changes more than and eight of an inch I would suspect a bent rim. You nee dto do it on bothe the inside and outside - but the best way is to take it off the car and have someone check it on a balancing machine.

The disc is harder because you need to remove the wheel and use a dial indicator

ORIGINAL: trapped

Also sometimes when im breaking at slow speeds i can feel the car lurching and slowing rather than just a smooth break.

Yeah, I experienced the same thing, both at speed and also slowing. It's definitely better now with the improved balance and wheel swap, but still there slighlty. I know the back 2 are stilll slighlty bent and the tires are out of round, but I'm wondering if I could have a bad disc too?

Fix one thing at a time. Since the shop said the tires are OoR I would deal with the first.