sebou

I bought this car with 173 000 km. Soon after it I had a puncture on one of the front tires, so I changed both front ones. From there on I started feeling a vibration in my seat coming from the rear. As I was changing the Timing belt etc. I asked the VW dealer to have a look at it, apparently the rear tires were starting getting oval. So I change them, still I could feel a vibration so I balanced all the tires. Still I could feel the vibration, I didn't worry too much and soon after I had to change the rear calipers, as I did with rotors and pads, I thought it would fix the problem but in fact it didn't. As I did the calipers I asked my VW dealer again to check that vibration and he told me the back tires were getting oval again. Apparently I had bought tires that weren't "good" enough so I replaced them and put the same as the one in the front (goodyear allegra). Still I felt a vibration so I balanced the four wheels again.

Now I still have that vibration in the seat coming from the rear. It is a slight bouncing in the beginning getting to a vibration starting 60km/h and then vibrates from 80 km/h to 100km/h with a peak at 90km/h. When I pass the 100km/h we don't feel it as much anymore but still can notice it.

I have no clue where it can come from anymore. I don't want to invest too much in that car as I allready spend quite a lot. And

Please give me some hints to find out what it could be.

thank you very much

seb

austinado16

1) Remove all 4 wheels, put them in a tire spin balancer, and actually watch what the wheel.....and what the tire is doing, for each one. You could have a bent wheel that balances fine, but will still be a bent wheel and cause vibration.

2) Measure the tread depth. If your car is a quattro, it can not have tires with different diameters.

3) If you have a quattro, remove, clean and inspect the rear axle CV Joints on both sides. Worn CV joints, especially the "inner" style that are used on both the outer and the inner on the rear axle, will "climb" up on themselves internally, causing a load related vibration. If you can get rebuilt axles, just replace your axles completely.

4)If you still have a vibration after doing the above 3 steps, remove, clean and inspect the front axles....or replace them.

5)If you have a quattro, don't over look the driveline. It has CV joints at each end and they never get serviced. When I looked at mine at 175,000 miles, the grease in the looked like dry black clay.

Good luck.

hammer 10

5)If you have a quattro, don't over look the driveline. It has CV joints at each end and they never get serviced. When I looked at mine at 175,000 miles, the grease in the looked like dry black clay.

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My Quattro only had about 70K miles on it when I bought it 2 years ago and the driveshaft CV joints had the exact same problem. My theory is Audi got a bad load of grease for the driveshafts. I used to rebuild wrecked bugs and worked on countless dozens of them, I also rebuilt 15 or so 914 Porsches and worked on a few BMWs and never saw CV joint grease get thick like that, maybe a little on the thin side but never turn into the black clay that Todd is talking about. At first I thought it might be the exhaust heat but I had the driveshaft out of my old Syncro several times and the grease was fine. It really surprised me and i'm willing to bet it's a common problem. ~ John Buchtenkirch

austinado16

It's pretty common in these "outer" style joints at high mileages. I find Vanagon joints like that quite often, and they'll start making noise too.

hammer 10

It's a problem I never saw on the earlier German CV joints, maybe they got nervous about the earlier CV grease thinning out ? I would like to think that they didn't cheap out but we know cost has become more of a concern due to the Asian onslaught. Stuff like this just bugs me, they had something that worked fine for years, why did they have to change it ? ~ John Buchtenkirch

sebou

OK,

thank you very much for your comments, I'll try all these during the week end and keep you posted, I think it should come from either the CV joints or it is really the driveshaft as I can feel this vibration on the shift and also in the pedals.

As I can't do it myself, I'll bring the car to garage and ask them to check, do you have any idea how I could ask them to check if it is either the CV joints or the Driveshaft? Any Idea of how much this might cost?

thanks a lot again.

austinado16

Start with the visual inspection of what the wheels and tires look like when spinning on the tire balancer, and then go from there.

You're going to have to do this one area at a time, then go drive it and see if it's fixed.

Regarding the CV joints, you really just have to take the axles out, take them apart, and inspect.

sebou

I forgot to mention that as we did the last balancing we switched the Rear wheels to the front and the front ones to the rear, after the balancing had been done.

In case the wheels would be responsible for the vibration wouldn't I then feel the vibration in the Steering wheel instead of the seat and whole car?

Wouldn't it mean that the wheel are out of question and that it is more coming from the rear axle? whatever it is , drive shaft or CV joints?

thanks for your help, this is greatly appreciated.

austinado16

You haven't said if the car is a quattro, so I don't know if you have a driveline, or rear axles.

Yes, typically if the vibration is due to wheels or tires, and you move them, the vibration will be felt more in other areas. However, since you've been trying to resolve this problem for a long time, and haven't yet, my suggestion is that you start from wheels first and then look at axles and then driveline.

sebou

Yes the car is a quattro, so there is a drive shaft and rear axles.

I'll do the steps you told me and keep you posted I hope I can do it this WE.