I drove across the country from California to Maryland for the Potomac Specialty (truly coast to coast) with 4 dogs in 3.5 days. We drove about 10-11 hours a day, had our route marked out for hotels, gas and breaks etc...
Of course the dogs were used to traveling, so that meant they weren't stressed, (so no whining, drooling, vomiting), they pottied on lead, were used to hotel rooms, Soft Crates, being fed in different places etc... We also made accommodations for them in their crates, while I usually don't put water buckets in car crates, we did to keep them well hydrated, and bedding in their crates, and toys like stuffies and Zogoflex to play with and chew. We got them out to stretch their legs and potty around every 3-4 hours minimum, on Flexi leads (that they were trained to, I usually hate them), and the rare fenced in dog park to really let them run, especially when it snowed on the way back, they loved that. They also got special treats like hard boiled eggs from the breakfast bar at the some of the hotels.
Bring bottled water, poop bags, any medications they use regularly, flea and tick meds, Benadryl for bees stings or spider bites, something for digestive upset, ear stuff if your dog is prone to icky ears, vet wrap and saline eye drops, think of anything they might need for a First Aid Kit for dogs. I have a tupperware container I travel with, that has everything I need to care for them, anything more serious and I look for a local veterinarian. Bring vaccine records, especially a Rabies certificate, and a collar with your cell number and an alternate phone number on a tag in case he gets away from you while you are traveling. Stainless steel dog bowl and water bucket, food treats, snacks. I always have extra leads and collars in the car too.