Thanks, I heard the train to when I went out to smoke. It was about 4 minutes before the train. The bang startled me. I've heard a high speed Collision before and thats what it sounded like. And you know how if someone is unconscious with their head laying on the steering wheel? That's what it sounded like. It was faint from where I am at by Algonquin and Lee. But if the wind is blowing right, it will carry the sound. It stopped about 5 mins ago. I called 911 to report what I heard. Sounded like it could of been over by Oakton and Elmhurst. In that direction.