IG4SE-22 STRUCK GOOSENECK TRAILER BEING TOWED BY A DENALI PICKUP TRUCK AT A PRIVATE CROSSING. THE TRAILER WAS TORN FROM THE PICKUP TRUCK AND PUSHED NORTH AND WEST. THE TRUCK WAS ON THE SOUTH SIDE ANDNOT IMPACTED BY THE TRAIN. THE DRIVER DID NOT SEEK MEDICAL ATTENTION AT THE TIME OF THE INCIDENT.HIGHWAY USER'S ACTIONS:STOPPED ON CROSSING (NO GATES).