GTA_Driver

I think there are 2 distinct problems: noise and vibration.

Control arms could cause vibrations, especially since you replaced the axle and both inner and outer CV joints.

However, I am not sure what kind of noise you're experiencing. A failed wheel bearing will provide a hum, almost a vibrational hum at very high frequencies. Think of inserting cardboard into your bicycle spokes to make the motorcycle sound as a kid, and going downhill very fast.

As you turn the steering to put greater load on the wheel bearing, the noise will get louder, and may be gone if you turn the wheel in the opposite direction to remove the load off that wheel bearing.

HOwever, you're experiencing a thump-thump-thump/flap-flap-flap sound... Does it sound like something is rubbing? Could it be your brake shield rubbing?

SixStick

Traveling straight its more vibration than noise, which increases its speed with speed of the car.

When taking a sweeping turn to the left, say on an off ramp, I hear a rub, rub, rub noise. I'd say it's almost metallic sounding. So perhaps the backing plate is bent a bit and rubs on something in a turn.

GTA_Driver

I dont remember if you did, but did you take the car in for an alignment? Excessive toe could cause all sorts of issues. Of course, you'd have to replace worn out control arms.

SixStick

It was aligned by Audi after I installed the two new outer tie rods. No improvement was seen.

So to review, here's what I've replaced thus far:
2 new outer tie rod ends
1 new right inner tie rod end
1 new right front drive axle (did left side last year)
Road Force balanced twice, spin balance once
Alignment by Audi.
Road tested and searched for source of noise and vibration by two indie mechanics and Audi dealer.

Still no success.

Is the only thing left to try is to replace are the control arms?

GTA_Driver

Is your vibration present if you throw the car into neutral at highway speeds?

SixStick

Yes it is

SixStick

Ok, so I bit the bullet and had all the control arms replaced including the sway bar links. The vibration is much better. But there still is some vibration and steering wheel shimmy. You can feel most it at 20 and 60 mph. Still can feel it when turning left.

So at this point I've replaced the following:
Tie rods (inner and outer)
Right front axle
Upper and lower control arms and sway bar links

Also had all four wheels straightened and trued.
Balanced tires multiple times.
Car aligned twice.

This problem arose when I put on a new set of Conti DWS tires and tried to have an alignment done. I even had Tire Rack send me another set of front tires to see if I had bad ones.

Audi and 2 other mechanics still say it's not a wheel bearing. Wondering if I should just throw another $400 at it and see if its the bearing. Not much else it can be.

Any thoughts?

Thanks

Prospeeder

Sure sounds like a bad wheel bearing, thats really all thats left. really should only be like 200-250 for one side. Or are you at the dealer?

SixStick

Yeah, looks like I should do the the bearing. Unfortunately in the metro NY area even the indie mechanics are fairly expensive. So $350 - $400 is probably about what it will cost.

I rarely visit the dealership for repairs. But to be fair, Storms Motors in Southampton, NY is very helpful the few times I do go in. They treat me like any other Porsche or Audi customer who drops bigs bucks with them – which I don't. I figure they would charge between $500 and $600 to do a bearing. I think they charge $150 and hour for labor. I'm guessing 3 hours labor and $125 - $150 for the bearing. Adds up quickly.

Thanks for your comment.

JRomulus

Any update on this vehicle / situation?
Did u replace the bearing?