I've noticed that when I am making a U-turn and I turn with the wheel all the way to the far side (in this case turning left, so the wheel is to the far left) the car starts shaking, as if the wheels are hitting something. This is the second car I've noticed it in, is this normal? Both cars were AWD (well the first car is a Jeep, I noticed it more when I was in 4WD), my A6 is a Quattro.

On a side note, yesterday I noticed a little noise (sounded like two things are rubbing against each other) when I turned the wheel slightly to the right, only happens at 10-20MPH and only if I turn the wheel slightly, maybe 90 degrees, ideas with that?

 

Check your outer cv boots. Make sure they arent torn. Does it make that noise when the car is stationary and you crank the wheel all the way to one side?

With the second noise does you esp light also come on at the same time?

 

For problem #1: What are the cv boots? And no, the noise/shaking is only there when I am actually moving and the wheel is turned all the way. I can confirm this happens when I am turning left, next time I'll turn right that way and see if I get the same shaking.

For problem #2: No, its just a faint noise i hear, it goes away after I turn the wheel a little more...

 

c/v boot in picture, judder is caused by full wheel lock "tyre catching inner wheel arch" don't do full lock its bad for the steering system

[IMG]local://upfiles/12092/FCF6380A823A40EDBCF742B7FE44430C.jpg[/IMG]

 

4 wheel drives have a biting from the front wheels when you crank them all the way to the side (for a u-turn) especially from a stop. I would assume that is your first problem. Not that the wheel are hitting anything, but rather they are biting at the pavement. That is natural with all 4wd. If it is making noises when making u turns, back off the steering wheel. If you hold it against the steering stop, you create a lot of torque on your system that can break brackets or something else (and makes your belts squeal).

 

Problem 2 could be a world of noises.

Check your power steering fluid to make sure it is full. Look for the CV boots on the front and rear axles (connected to each wheel and transfer case/ rear end.) (Check them to make sure they are not covered in grease. There are some metal plates around the brakes that rub up against the discs if they get bent in esp low speed... but that noise is fairly pronounced. There are also plates around the drive shaft.