{Chrysler 300} Ball Joint Follies

You know, sometimes this hobby is just not fun.

I have NOS upper control arms. I have two new ball joints. NOS control arms do not have any threading in them, the first ball joints installed cuts the threads. I have the miller socket for the ball joint.

So, I go to thread it in, and it will not go down even using my impact driver. It goes about 75% in and then will not go in more. So, I pull it out, take a small wire brush and clean out any swarf and try again. I then add Rapid Tap oil. I end up getting it in and down and torqued to 125 after four or five cyclers of in-out-clean-again. I pull it out and clean up the thread sone last time and then put it in and torque it. Ok. One down.

Now, I take the second control arm. This time I go to put it in, and it feels like mush. I can get it down just using the torque wrench. It seats but will not torque down and I can see it starting to dig into the flange on the control arm. I pull it out and it has barely cut in any threads. I did not measure the two smooth bores on the NOS control arms to see if they were the same.

So, I happen to have one NOS ball joint that came with one the arms I got from Dave. I fish it out and go to screw it in and it goes in hard like the first one. Not quite as hard. I do the in and out thing and wipe the swarf and then get it down all the way. I then torque it and it torques down fine.

The only real explanation is that the Q&A on the ball new ball joint threads is bad. One ball joint is either deeper than the other or the NOS control arm bores were not very close. I would guess it was the ball joint is the problem given that the NOS ball joint went in fine.

I am bothering to write this so that people know. You could get a set of new ball joints and screw them in, and they may not torque to 125. If someone uses the impact driver and does not double check it with a good torque wrench, you could end up with stripped threads in the control arm.

Beware.

James