My dog had a fear of riding in the car even when we went someplace fun. He would whine, pace and drool the entire time.
I've found if I keep him occupied in the car, he doesn't even notice the ride. So whenever we go anyplace longer than a 10-20 minute drive, I buy a large soup bone at the grocery store. He spends the entire ride chewing on the bone and doesn't even notice that he's in the car.