So what would y’all do? Slap a new nut and washer on? Good excuse to upgrade to PSC? I’ve not done anything aftermarket before. I’ve got little experience with steering components.
As suggested, I'd add a new nut/lock washer and torque to 185 ft/lbs.
Its funny you mention the PSC upgrade. When installing my JK axle, I went with a PSC box and a RockJock (TJ to JK) pitman arm. I checked both the sector shaft and pitman arm for burrs and both seemed to fit up well. When installed, I noticed the pitman arm seemed to engage a little lower on the sector shaft, but had full nut to thread engagement. The pitman arm was torqued and removed several times and it would not install any deeper.
When I returned home from the new build shake down run, it was apparent the lock washer had opened a bit (there was still tension on the nut and my paint marks still aligned). It looked like the pitman had moved up higher on the sector shaft. I retorqued the nut (with locktite) and was able to get an additional turn on the nut. After a second trail run, I noticed the lock washer had a tiny gap visable. I noted my paint witness marks were still aligned on both the lock and nut. This again indicated the pitman arm moved up the sector shaft. I reinstalled the lock, nut (blue locktite) and again was able to pull about another 1/4 turn to 185 ft/lbs.
After dealing with this twice, I am certain the RockJock pitman arm coating is the culprit. I am assuming the turning forces of the sector shaft splines to the pitman arm splines were enough to break the coating up and create a gap. This ultimately allowed the vertical movment of the pitman arm up the sector shaft. That said, I am fairly confident my pitman arm is fully seated now.
What pitman arm did you use on your axle swap?
I am sorry you went through that experience on the roadway and am glad you are ok!