When the steering wheel was first put into use in automobiles, it was called the "whip". The whip is what you used to control the horses on a stagecoach, hence the analogy. Many years later, various hip hop artists noticed that the Mercedes-Benz logo resembled a steering wheel. They then proceeded to use the old term "whip" to describe any Mercedes-Benz vehicle. The term has now been generalized to classify any expensive automobile. (Urban Dictionary)
"You get pulled over by the cops three weekends in a row. One time, they sit you out on the curb and you watch as all the other whips sail past, passengers ogling you as they go."
- Junot Díaz, "The Cheater's Guide to Love", New Yorker 23 July 2012