In my car, the dogs ride in crates. But when we go camping, we take Vince's truck. And the girls get to enjoy riding in the back seat. (Ein prefers to cower on the floor, because 11 years of car rides to countless awesome places have not changed his mind. Death is imminent! Vehicles are not to be trusted!) I bring a crate along for Ein, it helps him feel safer.
But what the girls love even more is when Vince and I leave the truck. For gas, for a food/bathroom stop. We usually camp in the fall and it is often cool enough to stop for a full sit-down meal at a diner on our way to or from wherever we are going. On those occasions we usually find both front seats filled with a dog each. But on shorter stops we take guesses, "Which dog will be up front?"
While we were securing and loading and hitching up the camper and packing everything for travel, the dogs were all loaded up into the back seat. We knew it was only a matter of time before someone moved up front. Just like she owns the place or something.