LCA Blues: Replacing lower forward control arms…10 steps to success.

2006 A4 B7 2.0T quattro, 188k miles.
Replacing the control arms on our A4 was quite an ordeal. I started all this way back in May 2020. I replaced the upper arms having to deal with the dreaded pinch bolts. Gawd! Those awful pinch bolts are featured in several website articles and YouTube vids. You may want to check those before attempting. Yikes.
I later bought the lower control arms. Three of the four went in without incident. The fourth, the forward arm on the drivers side, that one would not come out because the steel bushing wanted to pull out of the steering knuckle. When that happens the end of the control arm wedges against the knuckle and cannot be pulled out. I put the thing back together and thought about how the heck I was going to get the arm out. For several weeks!
I finally came up with this quick solution. I'm hoping someone else may benefit from this and save some headaches. As far as I know, nobody on the planet had thought of this method before.

The problem: Sometimes when replacing lower control arms the steel bushing (insert) mounted in the steering knuckle will want to come out stuck to the ball joint stud.
The forward lower control arm can be a big headache. If the insert starts to pull out, the end of arm will jam against the steering knuckle and will not clear. There is only about 2 mm clearance to start with. Cutting the ball joint stud off with a Sawzall or side grinder is one option but can be quite a hassle. Yikes, that’s a hardened tool-steel stud. Good luck with THAT. The method that follows avoids such headaches…

Ball joint bushing starting to pull out. (Yep. Those are my hammer marks.)


The solution: Here is a better way, and it’s easy. This takes about 15-20 minutes.

1. First loosen the sway bar at its mounting points. Just loosen the four nuts involved. (13 mm socket and 3-inch extension). Removal of the bar is not required. Disconnect the sway bar link from the sway bar at both the passenger and driver side. Now swing the bar down out of the way.


Important: There is a rubber oil line that runs parallel with the sway bar. The line is held in place with a plastic clip. Be gentle when swinging the sway bar down or the clip can break. How is it I know that?

2. Fully remove the sway bar link from the control arm.
3. Remove the lower strut bolt.
4. Remove the control arm bolt at the frame end.

5. Now you can swing the end of the control arm forward toward the front of the car, like this...go ahead try it...


6. Ok, now swing the arm back to its normal position and even a little past that. Then grind approximately 3-4 mm of aluminum alloy material from the end of the arm in the area facing the front of the car. I used my side grinder with a flappy abrasive wheel. It took just 35 seconds. I suppose a Dremel with an abrasive wheel or even a flat file would work but will require more effort.


This flappy disc worked really well.


7. Swing the arm pointing forward again. Your grind area has now about 5-6 mm clearance in this position and it will clear.
8. Remove the retaining nut then drive the stud and insert out together. My 17 mm impact socket fit just right against the insert as a mandrel. It required some mighty whacks, but it drove out okay.

Aha, got it out but the insert is still stuck to ball joint stud. Now what?


9. Remove the insert from the stud. This may take some doing. Do not be afraid to take it to a machine shop if you can’t get it off. It may be a bear to remove.
Achtung! Audi does not sell the tapered steel insert separately so be extra careful you don’t ding it up.

I used heat and a three-jaw puller. Not the best photo but you get the idea.

10. Now that you've recovered the insert, tap the insert back into steering knuckle. Install a new lower control arm. Reinstall-tighten sway bar links and mounts. Done. Hey, easy peasy….and no headache.

Success!