To dream of crashing a car represents conflicting ideas, goals, or situations. Your ability to make decisions or continue your direction in life has been hampered by someone. Relationships, friendships, or business decisions in conflict with similar goals.
To dream of other objects or vehicles other than cars crashing may reflect feelings about potential problems arising in your life. Failures. Conflicts or embarrassments. Fighting or arguments. A successful area of your life that has suddenly stopped. Conflicting agendas of different people colliding.
Example: A young man dreamed of crashing his car into another car. In waking life this mans’ friend found out that he was sleeping with his ex-girlfriend and he had to stop the affair. The crash reflected the conflicting direction of their lives coming to an end.