The problem is definitely with Apple Maps on CarPlay, and not the car type, or the specific car's firmware, the cable, the USB port, etc. Here's how I know: I've had this problem with an iPhone 7 and now the iPhone X. I had the problem on the iPhone 7 when running 10.x and then 11.x, and now running 11.1.1 on the iPhone X. I also see the problem in two different cars, a '16 VW Golf and a '17 Ford Explorer - exact same problem in both. And yes, I've seen it in random cars that I've rented ranging from Chevy's to Cadillacs.
What I'm seeing: I never see the map lock up while I'm actively following directions to an entered destination. I only see it while there is no destination entered and I'm merely displaying my current location on the screen. But when it happens, I'll suddenly realize that my location indicator is no longer on the screen because the map stopped following me a while ago. And it stays that way until I interact with it.
What causes it: I have not idea - there is no rhyme or reason as to what causes it to freeze. I don't think it has anything to do with interacting with the device because sometimes it will happen after not touching anything for a while. The frequency does not follow a pattern either. Sometimes I can make a whole trip without it freezing, other times, it will happen several times on a short trip.
How to resolve it: Very easy, I just tap the screen, and re-select the orientation to my preferred "icon always pointing up" mode. But then, like I said before, it will happen again even without any subsequent interactions.
Very annoying - looking for a solution to this, but haven't found one.
Still crossing my fingers waiting for the day when Apple will allow Google Maps or Waze in CarPlay.