One of the most awful risks of being on the road with a pet is the chance of injury or death, to you or your pet. And not much ups that risk more than allowing a pet to roam loose around the cabin. Cats and dogs not secured in crates, cages or pet-specific restraint systems can become projectile pets. If a 60-pound (27-kilogram) German shepherd is loose inside a car traveling at 30 mph (48 kph) and there is a collision, that dog can cause an impact of 2,700 pounds (1,224 kilograms) -- an impact into another passenger or into the windshield [source: Bark Buckle UP].
Also, no matter how much they beg, pets should never ride shotgun -- restrained or not. Air bags are designed to protect adults. During a collision, they deploy at 200 mph (321 kph). That's no match for children or pets who could be injured or killed by the force [source: PetPlace].
And dog owners listen up: Dogs shouldn't be allowed to ride in truck beds where they may fall or jump out, or if restrained, choke. Nor should they be allowed to hang their heads out of car windows, increasing their risk of serious injury from flying debris -- anything that has or could hit your windshield could also hit a dog's head.
Lastly, pets left in unattended cars risk severe injury or death from heat stroke and dehydration as the inside temperatures rise. If you're not in the car, your pet shouldn't be either.