Tamm, please give some thought to all that's been said above. Truly. You have a dog who speaks a whole different language than you do. We bring dogs into our lives and ask them live along side us, according to our rules. We give very little thought to their world, their rules, their language. And we must remember, they do have a world all their own. Often times, what happens is, when they don't live like we think they should (when they do something "wrong", like bark at people from cars), we "correct" (punish) them (by spraying them with stuff attached to their collar) so they won't do it anymore. It would be much kinder to spend some time - build some communication - and ask the dog not to do that anymore, by introducing a different behavior instead (show them how - in a kind way - to live in our world, as dogs don't have cars in theirs). By using a clicker and reward, you can reshape it's current behavior into something different/new ... and more pleasurable to you (and passengers and passersby, and actually the dog too), as everyone's stress level will go down, and relaxation will prevail. Just some food for thought. We'll help you as best we can thru this, just let us try, ok? Your dog is begging you both to read this, right about now.