How long do you see yourself as a truck driver?

Interviewing and on-boarding is a costly and time-consuming process for any company and, in the trucking industry, training is costly. Assure the interviewer that you are seeking a long-term fit.
Take a look at the various driving opportunities with the company. If any of these stand out to you, it's a great idea to mention them to the interviewer explicitly. Your expressed interest in those particular routes or opportunities will solidify the fact that you are, indeed, seeking a long-term fit with them.

"I am looking for a long-term fit in my next position. As you can see, I had a strong tenure with my previous company. I would love to see the same success here. I did notice on your website that you have long-haul opportunities across the coast. If I could work my way into a role like that, I would be thrilled."