How do you get a pit bull from barking at people and passing cars?

You simply just have to train your dog to behave and just because its a pit bul doesn't mean anything. They behave all on their own. But sometimes you can just say a command Word such as (Be nice or Enough) in a loud firm voice. But don't be to harsh and if your dog doesn't respond don't flip out. Just simply keep saying that and if that doesn't work you need to figure a way of telling your dog your the boss, but also in a kind way.