Wheelman is
thieves cant, criminal
slang for
driver. A competent wheelman steals a
clean car before the job, drives it expertly during the
getaway, and dumps it in a safe way after the job is done.
The importance to the success in any criminal enterprise of a good wheelman cannot be underestimated.
A good wheelman never steals a car for joyriding or for his own pleasure, nor do they steal cars for direct profit such as resale to a chop shop. That sort of thing is for amateurs.