Eating while traveling

When Loki was 8 months old, we took him on a 10 day trip back to Colorado. We had 4 solid days in the car and the rest divided between our families, so not much rest. He was playing with other dogs the whole time we were in Colorado, so getting a lot of exercise. We took 40 cups of food with us (he used to eat 4 a day) and came back with about 25-30 cups. Travelling throws off their routines and they don't seem to want to eat. As soon as we got home, he started eating normally. But whenever we're away from home, he stops eating again.
 
The only suggestion I have is to take along things that are familiar to him (ie toys, bed, dishes), so he will have some stability. I don't think dogs will starve themselves, so when he gets hungry enough, he'll eat.

It sounds like he was probably just stressed out with the change in routine, environment, your attitude (cuz vacations and traveling bring out some different aspects in many of us), etc.  The fact that he returned to normal eating when you got home is a good sign that it wasn't an infection or something he picked up on the road.
If this was his first trip, it's not surprising he'd be stressed.  He may likely be less stressed on your next trip, or he might repeat.
Make sure he stays hydrated - especially in this heat, if he stops drinking for too long, you've got trouble.  Bring the stuff that he is familiar with - is he crate trained?  That helps many dogs have their own space to go to when they feel unsure.  Nothing inside the crate changes - it all smells like home.  It can be reassuring.  Not that you have to close the door on him, but that he has that space reserved for him.