Max cried in the car his entire first year. Giving him a dog car seat helped a lot, and then having his brother to share it helped.
Try opening the window just a little bit to give him fresh air. Take short car rides daily and lengthen a little at a time. Give him a favorite blankie or toy in a car seat. You can also ask your vet for a prescription med like Cerenia, a motion sickness med. Or talk to your vet about using Benadryl (make sure you use the right one, no additives, which can toxic to dogs).