Don't let your dog travel unsecured in an open pickup truck bed. Dogs can't "hold
on" the way humans can, and any sudden start, stop, or turn can toss your pet onto
the the highway. If the impact of hitting the road at a high speed doesn't kill
it, oncoming traffic probably will. It is estimated that at least 100,000 dogs
die this way each year.There are other hazards to consider. Most dogs love the feeling of wind blowing past their ears at 60 mph, but that wind can seriously irritate mucous membranes and blow peices of grit into the animal's eye. It may require veterinary attention to remove the foreign material, which could cause permanent dameage to the eye. Insects or flying debris can also lodge in the nasal passages or get sucked up into the windpipe.
Open truck beds provide no protection from the weather. Rain snow, and freezing temperatures are obvious problems, but even warm days have their dangers. Hot sun can heat the metal floor of a truck bed enough to burn a pet's paw pads. And once the truck has stopped, a dog left sitting in the broiling sun without water or shade may suffer from heat stroke before long.
It is safest to allow your dog to ride inside the truck cab, or leave it at home. If it must ride in the back of the truck, put the pet inside a crate that will give it some protection from the wind and weather, and tie the crate securely to the walls of the truck bed so it cannot slide about or be tossed out of the truck.