"I have worked on automobiles since I was a kid. My father was a mechanic, which spurred my interest at a young age. For the past ten years, I have held a formal role as shift lead at the same auto body shop, working primarily on domestic cars, trucks, and SUVs."

If you haven't worked on automobiles in a professional setting, don't sweat it! You can include your experience working on your own cars or others. When you respond to this question, you want to go in depth about the type of work you have done, sharing your knowledge and areas of expertise.
Rather than saying: 'I have about 8 years of experience,' Instead focus on specifics: 'I've been doing general maintenance and repairs in foreign and domestic cars for about 8 years. I specialize in X, Y, and Z.'
Sell yourself! Share what you have learned over the years. If there is something you are interested in learning more about, let them know. The interviewer wants to hear you are passionate and genuinely enjoy what you do.