What is the purpose of setting your parking brake when you park?

Setting your parking brake when you park is essential for safety, as its primary purpose is to ensure the vehicle does not roll away. When a car is parked, especially on an incline, relying solely on the vehicle's transmission to hold it in place can be inadequate. The parking brake engages the rear wheels, providing an additional layer of security against unintended movement.

Using the parking brake helps prevent accidents, protecting not only your vehicle but also others around it. While some of the other options may have relevance in different contexts—like fuel conservation or wear on tires—the driving principle behind using a parking brake is to maintain stability and security in a parked vehicle. Additionally, while a parking brake can act as a deterrent against theft, that is not its primary design function, reinforcing the importance of its primary role in vehicle safety.