Here are some degrees that can help you realize your dream of working with cars:
Automotive Engineering: This could be anything from designing the engine, to how a car gets better mileage, to improvements that consumers want, to safety features. For example, someone had to think up the idea of seats that folded down to make a flat surface, and figure out how that would happen. Glass that shatters into small pieces rather than breaks in shards was someone's invention, as were air bags, head rests to help avoid whiplash, outside temperature display, digital compass, and remote door locks.
Other engineers work with the actual materials used to make cars: what is the lightest? Most durable? Flexible or not? What paints last the longest? What will make the interior work best?
You can also contribute to the automobile industry with a degree in Product Design, Automotive Design, Industrial Engineering, Electrical Engineering, and CAD (Computer Aided Design). Other degrees that might land you a job with an auto manufacturer include Math or Environmental Science. Tech Schools have courses in Auto Mechanics and Auto Body Repair as well, which would give you hands-on experience and knowledge of how cars work.
Will help you do this:
You might get specific, thinking about:
Design of Interiors: What kind of car do you like to work with? Luxury cars, economy cars, 'sports' cars?
Design of Exteriors: Have you thought up a different looking auto body you think would sell?
After working up a design on a computer, models are first made in a small scale, and eventually a full size model or prototype will be made. You might enjoy this phase of design---testing out the car to find problems as well as to see what works.
Pretty sure this is no good in snow.
Keep in mind there is also a market for specialty cars, such as police cars, armored cars, ambulances, fire engines, and cars for the handicapped. Do you have some innovative ideas to bring to that table? You might have a problem using a car or know someone who does. How would you design a vehicle for a specific purpose or person?
And don't forget 4-wheelers and other sports vehicles; that's a fast-growing industry that will want more designers and engineers as well.
Sometimes film makers want a fantasy car for a movie. Are you super-creative? Could you design the next Batmobile??
If you could land a job working with a manufacturer, you would be collaborating with many other people in coming up with a final design. Be sure that you can be tactful and diplomatic in this area, and assertive when you need to be. Others will have ideas that can compliment yours, and vice-versa. You need to be creative, and to be strong in communications as well as the technical aspects of automotive design
Colleges offering automotive engineering include:
University of Michigan
University of Indiana at Purdue
Kettering University (Formerly General Motors Institute)-Flint, Michigan
University of Texas-Austin
You might also try getting in touch with specific manufacturers; ask them how to meet your goal of working with cars---maybe for that manufacturer---one day. Some have training programs specific to their brand.
http://corporate.ford.com/careers?&ccode=US Ford Motor/Corporate (they have internships)
http://careers.gm.com/career-tracks.html General Motors
http://www.chryslercareers.com/Pages/default.aspx Chrysler and Dodge
If you have the drive, you can make a career working with cars!