My dogs get harnessed in so they can't move around the car to much. They can still stand up and turn around to get comfy. When we have the dogs on a long car ride we stop every 2 hours, for about 10 minutes. We give them water then, let them potty and walk them around to stretch their legs. I also bring their nylabones and they do often chew on them in the car. I also like to bring some towels or paper towel, a collapsable crate and extra collars and leashes just incase.