How to Correct Car Herding Behavior

Question
Hello - We have a 2.5 yr old Australian Shepherd who loves to pass the day away outdoors running back and forth the front of our yard bark and "herding" vehicles.  Fortunately we live on a private road and there is only one other house beyond our property so there is not a dangerous traffic flow.  But there is regular flow of vehicles since both my neighbors and us have home based businesses with some comings and goings of customers and employees; along with regular traffic of mail carriers, garage trucks and family and friends.  We have an invisible fence installed which our dog respects, thankfully.  The annoyance is the vigorous barking when people come and go, the nipping of tires of the vehicles that come in our driveway and the mud trail that circles our yard frontage and up the driveway.  People not familiar with our dog think we have a vicious pet which isn't the case.

The first couple years I took him to obedience classes and agility training, which he really liked.  He also has some dominant dog aggression issues, which is another story, so we had to drop the agility classes since I had troubles jumping through tires on a leash :-) .  He enjoys being outside so I like to let him stay out to get exercise (but not the car chasing exercise!).  We have tried addressing the problem by putting him on a long lead and then correcting him until he stops chasing but he quickly goes back to his old behaviors when not on a lead.  He gets lots of playtime w/us and our two children so I don't think he is bored.  We bring him on our vacations so he is very much part of the family pack. Do you have any suggestions on how we can effectively address this unwanted job he has decided needs to be done?  Thank you in advance!

Answer
Car herding is an extremely difficult behavior to correct because it is a genetically based instinct and is highly self rewarding.  The first thing one does in order to correct a behavior is to prevent it from repeating.  You need to keep this dog in the house unless you are willing to accompany him outside.  The second thing ones does is to CAPTURE the behavior and redirect it.  In other words, he needs a JOB.  He needs to be trained to herd benign objects.  Large beach balls are WONDERFUL for the herding breeds.  I'm afraid your dog's intellect isn't being engaged and of course the threat is he will be seriously harmed while nipping at tires.  You need the expertise of a behaviorist who can come to your home and teach you how to re-shape his obvious strong need to control.  I can't possibly instruct you in this venue.  Much luck with this!