Keep your dog contained in a secure kennel or fenced yard so that he can’t chase vehicles on the road.
If you walk your dog off leash, do so only in places where he isn’t able to see or access roads.
Teach your dog a really reliable recall so that you can call your dog whenever you need to. Please see our article, Teaching Your Dog to Come When Called, for help. To be successful, you’ll need to start your dog’s training away from traffic areas so that your dog can focus on learning about the benefits of coming to you. Only when your dog is extremely reliable at coming when called should you “test” him around traffic. Even so, be sure to take him by roads only on a long line (a 15-foot or longer training leash) in case he doesn’t respond to you.
Please note: When dogs learn to come when called under relatively calm and quiet circumstances, they often don’t know that your cue “Come!” means the same thing when they’re in very exciting and distracting circumstances. They’ll chase the car, and then come to you. Because of this, it’s nearly impossible to call a dog off once he’s in pursuit of a car. Be prepared to devote a great deal of training time and effort to teaching the recall. Even when your dog does come when you call, realize that he’ll still be motivated to chase cars. It will be your responsibility to make sure that you detect a situation early enough to call him back before he takes off.
One last resort option is to teach your dog to associate chasing cars with an unpleasant or punishing experience, such as an obnoxious noise, repulsive spray or something painful. Although devices that deliver punishing experiences to dogs are available online or in pet stores, it’s crucial that you work with an experienced CPDT trainer or certified behaviorist to ensure that the treatment is humane and effective. (Please see our article, Finding Professional Help, for help locating a qualified expert in your area.) The behaviorist or trainer must work with your dog over many sessions, in a variety of circumstances with different cars on different roads, in order for the procedure to make a difference in his behavior. Some dogs are so highly aroused by the anticipation of a chase that even associating cars with very strong or painful punishment won’t keep them from chasing. This is why it’s so important to work with an experienced professional. She or he should be able to determine in the first few sessions if this procedure is likely to work for your dog.
What NOT to Do
Do not expose your dog to moving traffic and physically beat him. This is inhumane and highly unlikely to deter your dog. At best, he might refrain from chasing cars when you’re nearby, but he won’t learn not do to it when you’re not around. At worst, you could injure your dog, damage his trust in you and cause further behavior problems, such as fear and aggression.
Do not purposefully let your dog to take off after a car and then allow him to hit the end of a long line at a dead run. This could cause severe damage to your dog’s neck and vertebrae.
Do not attempt to frighten your dog off chasing cars by intentionally “bumping” him with a car or throwing something out of the car window at him. You could end up seriously injuring or killing your own dog.
WebMD Veterinary Reference from ASPCA Virtual Pet Behaviorist
The ASPCA Virtual Pet Behaviorist specializes in the resolution and management of pet behavior problems only. Please do not submit questions about medical problems here. Only licensed veterinarians can diagnose medical conditions. If you think that your pet is sick, injured or experiencing any kind of physical distress, please contact his veterinarian immediately. A delay in seeking proper veterinary care may worsen your pet's condition and put his life at risk.
If you are concerned about the cost of veterinary care, please read our resources on finding financial help.