Parking On A Hill: Engage Emergency Brake First

If you are parking a car that has an automatic transmission on a hill, apply the parking brake first -- thus allowing the brakes to do the job of holding the wheels in place so that the car does not push the "parking pawl" (ratcheting mechanism that locks the output shaft of the automatic transmission when it's engaged) ... to the point where it's difficult to disengage.  [I suggest first putting the transmission in neutral while holding your car in position with the main brakes using the right foot and only then fully engaging the emergency brake. Slowly ease up your right foot to test the holding power of the emergency brake. If it's holding the car firmly in position, then put the car in Park... ].

http://www.lowellsun.com/autos/ci_21541868/click-clack-talk-cars-can-mom-be-right

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