A dog chasing cars can mean serious trouble. More often than not, these dogs will be in prey drive mode and will try to catch the wheels, risking to be run over. Chasing cars, therefore can turn into a dangerous ordeal and may have a bad ending. Most importantly, a dog should not be allowed to chase cars in the first place, so if a dog is left loose off leash he must be put back on, if a dog is left alone outside, he must be placed in a safe fenced area.
Having said that, even dogs on leash may still have a tendency to chase cars. The solution to this is called: leadership. A dog should not be pulling its owner and attend to things to be chased. Rather, a dog must stay by its owner side and be under control. What if your dog will pull you towards a dog and cause injury to it ? or worse, what if your dog pulls and breaks loose to chase a child?
A dog pulling to chase cars is generally a dog with a strong prey drive that will tend to chase anything that moves. Trying to train a dog to no longer chase cars can be quite a challenge. The dog will need to learn to focus on something else as he is counter-conditioned. In other words, an owner should try to expose its dogs to as many cars as possible and teach the dog that cars are no longer interesting.
A good way to start is to put your dog on leash and walk on a road that is not too heavily trafficked. As a car approaches, the owner must be prepared to prevent the action of chasing. Physical cues such as ears pulled forward, anxiety and a tense body should be carefully observed. Different approaches should be tried to see what works best.
1) Use treats
As soon as the car approaches, get your dog's attention by showing him his favorite treat but without giving it. Timing is very important here. You want to act right before the dog acknowledges the car and gets prepared to chase. Show the treat and have him walk with you as he looks up at the treat. His attention should be on you and the treat. Then once the car passes give the treat.
2) Redirect attention
If your dog is not too food oriented, as the truck approaches and your dog gets tense turn him suddenly and walk in the opposite direction. This will take away the chasing instinct since the dog will be distracted by your sudden turn. After repeating this several times your dog will have learned to not focus much on the car.
3) Put your dog in a sit
As the car approaches let your dog sit and tell him to stay. Then get his attention by showing him his favorite toy or a treat. The dog should be focused on the toy or the treat and the sit will keep him relaxed. Once the car passes, give the toy or the treat.
It takes time, patience and lots of effort to condition a dog not to listen to its prey drive. A very important factor is to anticipate the dog. If your dog starts already trying to chase the car in his mind he has already had his own "prize". In other words, the action of chasing has rewarded him because he will think that he has successfully sent the car away. So timing again is very important.
When behavior problems as such arise, avoidance is not the solution. Nor are gentle leaders, pinch collars or electric collars. The solution is simple: you must show leadership skills, the ability to control your dog and the willingness to expose your dog to the problem rather than avoiding it. Once the problem has subsided, you will have a much more respectful and collaborative dog.