Here's what one dream dictionary has to say:
Trains:
+ Seeing a train in your dream, represents conformity and go along with what everyone else is doing. You have the need to do things in an orderly and sequential manner. In particular, if you see a freight train, then it refers to the burdens and problems that you are hauling around.
+ Dreaming that you are on a train, is symbolic of your life's journey and suggests that you are on the right track in life and headed for the right direction. Alternatively, you have a tendency to worry needlessly over a situation that will prove to work out in the end.
+ Seeing or dreaming that you are in a train wreck, suggests chaos. The path to goals are not going according to the way you planned it out. Or you may be lacking self-confidence and having doubt in your ability to reach your goals.
+ Dreaming that you are the engineer means that you are in complete control of a particular situation in your waking life.
+ Dreaming that you miss a train indicates missed opportunities or nearly escaping your death.