Jack88

I suppose I should really laugh, it's pretty stupid.

The shop didn't tighten the bolt for the aft front driver's lower control arm, they just had it on finger tight. I didn't check all the nuts they had touched, just one. It had been working itself loose the past couple weeks, making the noise worse and more frequent. On the bright side, very easy solution. I did find out my forward driver's upper control arm has a bad ball joint, it has vertical motion where none of the others do, so that probably explains my light freeway speed vibration. Easy fix! Hopefully, getting these things sorted means my suspension will finally behave as it should be. I am waiting on the Wabco rebuild kit for the compressor, I got a weird code the other day, something about an implausible signal from the ride control during a self test, greyed out suspension options for a trip on me. Given the car seems to take too long to change its height, I figured a rebuild was a good idea.

Dalplex

MP4.2+6.0

Good to hear. If you need the ball joint end, that means whole control arm. In that case, the Lemforder OES one is somewhat less than discounted dealer like audiusaparts.

Did you pull pinch bolt to really check out carefully? Will need to pull pinch bolt anyway if you haven't recently--in case you find it stuck. I have concluded to really check the upper arms out, especially the bushing end that wears like bad clockwork, pulling pinch bolt so they are free to move by hand gives you a lot more confidence in identifying issue. Same with tie rod ends where once they are loose you can usually feel even small tolerance issues or any hang ups, particularly on the inner one where no physical inspection is otherwise really feasible.

Jack88

Oh yeah, that pinch bolt was out recently. It's brand new and was greased well before reinstalling. In addition to the lower control arm bushings, I replaced all the upper ones as well. I'm thinking that boot that was torn could have been torn from long before I touched it and the joint had already failed, possibly damaged when the strut was replaced before I took delivery. I'm really sure it's bad, it definitely moves different than the passenger side one, which stays tight and actuates smoothly through it's full range.