I’ve had this problem since I had an episode of death wobble and they replaced the steering angle sensor twice and the pitman arm has come loose three times now. Every time a new nut was installed and torqued up to spec and tighter the last two times. With locktite as well. The last time it came loose after about 200 mile of in town driving, never over 50 ish. We noticed when putting another new nut on it got really easy to turn closer to the pitman arm. We suspect something isn’t quite right with my sector shaft and will now be replacing my steering box. I also have a dual steering stabilizer as well.
It throws a whole slew of codes when that happens including stuff from the abs module so it can be tricky to chase but most of the time we put the truck back on ids the steering angle sensor is off from where the steering wheel actually is.
I know this has nothing to do with your newest mods but I see you have a leveling kit and big wheel setup. Before you go diving off on a tangent, double check your front suspension. Get somebody extremely competent to help you shake down the front suspension.