Hello,
I am getting the exact same issue. (2018 model.) I had it at the dealership a month or to ago and they checked the electrical system to the power assist motor. Checked grounds and a recall which was done by them. All ok. The problem happened with the mechanic and I in the car but they said they have no answer. This problem started 9-12 months ago and is getting worse. It's going back to the shop Thursday 4/16 for other maintenance and they are going to look at it again.
What I did notice is a clunking noise when driving through say a grass lawn or bumpy road. It sounds like a bad tie rod end but they say they are 100% fine. You also can induce the clunk when sitting still and turning the steering wheel back and forth left to right. The shutter in the wheel DOES happen at slow speed say turning out of a parking place. The mechanic said the servo motor on the steering rack may need replaced which means the steering rack itself will need replaced. They are estimating 3-4K. Yes thousand. The van is 24 months old with 54K miles all highway. NOT ACCEPTABLE!
There is an issue with the design is my opinion. I am a trained aviation mechanic and there IS something mechanically wrong. I am beginning to feel it on the highway when slight bumps are encountered.
I did tell the shop I would wait for it to get worse and it has.
Chrysler cares please contact me so I can give you the dealership it is going to.
Karl