Originally Posted By: threeputtpar
You can replace just the bushings, but by the time the bushing is junk the ball joint on the other end of the control rod is toast. Much quicker and cost effective to replace the entire control arm.
My guess would be that when the shop changed your axle, they pulled the pinch bolt that secures the two upper BJs to the steering knuckle so they could get the axle out of the hub. The pinch bolt is almost always corroded in there and difficult to remove, and they may have used a torch to heat it. That may have toasted the 2 BJs, causing the noise you hear. It is also necessary to tighten all bolts through the bushings while the car is at ride height. They shouldn't have had to loosen those bolts, but if they did and tightened them while the suspension was at full droop that would have killed the bushings.
It may be time for an upper control arm kit to be installed. I'm doing the same thing on my A6 right now because the bushings are clunking in turns.
It's very hard to know what happened. The garage isn't saying much, and I don't if it's because they don't want to tell, or simply don't know what could have happened. I took it in today. They checked to see if something was loose and lubed all around. They seemed to think that that cured whatever the problems was. They said that they didn't think the slightly cracked upper control arm bushings were the culprit for the creaking. They said to bring it in again if it still creaked.