Having a Yorkie who is terrified of thunder and fireworks and other strange sounds, I can sympathize.
I tried googling "dog fears driving in car" and came up with several articles that discussed it. Here's the first:
http://www.apbc.org.uk/article3.htm
If you think this is a learned behavior, i.e., a bad experience in a car the first time, a trainer might be able to help. My guess is it's an unusual behavior and a behaviorist would be better suited. Definitely check out the Web, though.
Good luck, and let us know what you think.
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Mike ~ Doting Dad to Jillie, Harper, Molly, Cooper, Eddie (RIP), Lucy (RIP), Rusty (RIP) and Jack (RIP).
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