...and it maybe too late for nerdwerds's game, ...
Yup. I went with the idea that the Driver can sense the threat type of a vehicle, but I didn't give it to the player as a move. Whenever he gets into a car I just say something like "You feel like this buggy wants go fast" for a
ferocious fucker or "You feel like this APC wants to crush skulls" for a
vicious bastard and I've found that it provokes the player into asking questions and making moves. Which is kind of what you want players doing anyway, so it works perfectly!