Wishbone ball joints.

no not realy. there is 4 nuts that hold them on. 1 at top 3 at the bottom. undo the top one then get a ball joint splitter and seperate from the hub. undo the 3 underneath and its out.

when i did mine i replaced the hole wishbone, they arn't exspensive from you'r local car shop.
 
On the A3 it's a little bit more of a pain. As the ball joint sits closer to the driveshaft than on the S3, sometimes the you need to pull the drive shaft out of the wheel bearing housing if the top nut doesn't want to budge.
 
Thanks for the replys chaps, the only reason I will change just the joint and not the whole arm, is that a new one came with the car.
 
Jacked car up and took off the wheel to change the joint only to find that it looks like a new wishbone, so no need to fit the joint, result.