When motor vehicles do unexpected things, tragedies can happen. Rollaway accidents have injured or killed people of all ages. They have triggered other accidents after rolling into busy traffic, and have caused property damage. Worn parking gears in automatic transmissions may cause vehicles to slip out of park. In cars built before September 2010, automatic transmissions can be shifted out of park if the key is left in the ignition even though the engine is off and the your foot isn’t on the brake. There are many situations in which.