Originally Posted by MR.nismo

I bet no one knows this......
If you want the passenger to STFU, all you have to do is (while in a safe zone/area to do this) do a quick input in the steering wheel of hard left followed by a hard right. The passenger's head (the side of the head) will hit the glass. They will get the message..
I do it to my wife whenever she starts bickering or annoying me. She gets the message.