You can ask, but you're probably better off asking if they have "reliable transportation", or "are there any difficulties in getting to work" or something along those lines. It really matters why you're asking.

I've known of managers who have someone checking the parking lot to see what kind of cars the applicant drives, so it's not like someone is going to narc on you and nothing would come of it if they did. But if you didn't hire someone because of their old car, and they were members of a protected class, there could be a problem. And we're not supposed to inquire about their personal financial status - what kind of car you have is an indicator of that for a lot of us.

Suppose you wanted to hire someone who will bike to work (and I wouldn't blame you for that!) and you asked in the interview if she was a cyclist and had she ever considered bicycle-commuting, and it turns out that she has a disability?