Thinking back over my years of doing mechanical inspections at the roadside, one of the most common deficiencies in older vehicles was a parking brake that was either seriously out of adjustment or didn't function at all. Also known as an emergency brake, this mechanical alternative to your hydraulic braking system really has two jobs: providing emergency braking in the event of brake failure and holding your vehicle stationary when it is parked. Will your parking brake be up to the job?
The hydraulic braking system of modern vehicles is highly reliable with proper maintenance. It is actually two separate braking circuits that provide redundant braking if one half of the system were to fail. The parking brake is much less capable, even when it is in proper working order. Let it fall into disrepair and you cannot expect it to be much help when you finally do call on it in a dire emergency.
Many drivers don't realize that the parking brake acts on the rear wheels only and this can result in exciting consequences. The end of your vehicle with the locked wheels is the end that wants to be first. Apply the parking brake immediately with full force and you could find yourself zooming along facing backwards! Always apply the parking brake carefully in an emergency stopping condition.
Scheduled for a driver's test? Remember your parking brake. If you don't apply it when you park and release it before you proceed, expect demerit marks on the test result. A defensive driver will always apply the parking brake, even when leaving the vehicle parked on level ground. Reference Links