mmmmm, If u turn left and the sound goes... it should be the left side. (When turning the inside tire always turns at a lower rpm than the outside tire, so when the outside wheel has the bad bearing, the noise will become worse because that wheel is turning faster. so turn RIGHT and if the noise increases it again will denote a LEFT bearing that is gone.

On very bad bearings (as urs is) you should be able to jack up the front of the car and turn the wheel by hand and hear it grind, or place a hand on the suspension spring and feel any vibration.

I shouldn't bother changing them both, just the one that has gone. You never know what the previous owner did before you! Usually one hour labour plus parts is enough on a A4.

 

The front bearings are interchangeable, right? As in, if my mechanic orders one bearing assembly he can install it on either the right or left, depending on whichever one is bad?

I asked him if he should order two just in case, but he seemed pretty confident that only one had gone bad, judging by the symptoms I had told him.

 

[QUOTE]A worn Audi wheel bearing or Audi wheel bearing hub has a specific symptom. A loud humming noise. When this loud humming noise begins to come from the front or rear wheel area, Audi wheel bearing repair is inevitable.

Loud Audi wheel bearing noise can be tested as follows:
As you drive your Audi at a slower speed (25-35 mph) you'll hear a deep humming or howling noise. As you increase your speed (55-65 mph) the noise will change to a high pitch whining. This change in pitch indicates that you have a bad Audi wheel bearing.

How to figure out which Audi wheel bearing is making noise can be tested as follows:
After achieving a speed were the howling noise increases, load either the drivers or passengers side of the vehicle. For instance, when turning your Audi around a right hand corner your loading the vehicle weight onto the left hand side. Listen for the wheel bearing noise to increase and try to determine if it is coming from the front or rear Audi wheel bearing. You can also try swerving your Audi from left to right in a safe area and under safe conditions. Doing this in an empty parking lot can help determine which Audi wheel bearing is worn. If the side that the load is on makes an increased howling noise on the loaded side, this confirms that Audi wheel bearing replacement is necessary. If you're still having a difficult time determining which side the Audi wheel bearing noise is coming from, it may be necessary to replace both the drivers side and passenger side Audi wheel bearing or Audi wheel bearing hub assembly. To learn how to replace an Audi wheel bearing or for Audi wheel bearing installation techniques read the below information.[/QUOTEhttp://www.blauparts.com/audi/audi_wheel_bearings/audi_wheel_bearing_kit.shtml

And, yes, the bearings interchange.

 

The noise is about the same while I'm driving straight and turning right. It does get quieter while I'm turning left though. I'm guessing this means it's a bad left front bearing.

 

Correct.. left bearing.

 

Changed out and sounds great! No more grinding noise.

 

I had the same problem and it was my bearing but i tried to replace it without reading? duh> if you you have quattro you need a press to get the rear bearing out and back in. if u have fwd you are straight.

 

I was going to do mine myself, but I just didn't have the time or the right tools.

 

Update: It's been a couple thousand miles and it's already time to change out another one. This time it's on the right side, and I'm thinking it's probably the rear one, as the noise is just slightly louder toward the back.

I think I'm going to garage my Audi until I have the money to upgrade my struts, springs, control arms, wheels, and brakes. That way I can just replace all my wheel bearings and tie rods all at once so I never have to worry about them again.

 

that suck dude. I did roughly the same thing. The car just didn't drive right a couple of months after I bought it. Had a clunking noise coming from the rear and noticed the front control arms were squeaking WAY too much. I replaced the entire front suspension (New Control Arms, Springs, Shocks, Rotors and Pads) then did the rear (Shocks, Springs, Rotors and Pads). I also noticed my front bearing were a little worn so instead of ignoring it I fixed those as well.

If it doesn't f*ck with your schedule then by all means, wait and do it all at once. It sure beats having to service your car every week.