Our new Australian Shepherd has a new collar these days. We just couldn’t break him of chasing cars on the road. Rather than have a dead dog, we bought a “training collar” (which is a nice way of saying shock collar). Before, when he chased cars, he immediately got stern warnings and locked in the garage, losing his freedom. So after a few rounds of that, he would chase the car against our commands, then run in the garage to get his punishment!
It seems to be working. We’ve had it on for a little less than a week and I’d say the chasing has almost (but not quite) completely stopped.