Bro that's exactly what I do. I'm always super friendly at meet-up, say Hi , how ya doin, where ya going. Then I throw a feeler out there, weather usually or something else general. You can always tell how they respond if they're interested, or not, in chatting. If they are friendly and seem enthusiastic, of course the conversation will just flow. If they're not, then I just shut up and drive. Honestly it's worked super well for me so far. If they want to talk, I always talk. If not, just get that vibe and keep the radio on low. Agree it is tricky. And pax shouldn't rate low for it unless the driver is being obnoxiously annoying.