Tractor Trailer Underride Accidents. What is a Tractor Trailer Underride Accident?Tractor-Trailer underride accidents occur when a passenger vehicle, usually the front of the passenger vehicle, enters below the base of the trailer of a large truck (e.g., 18-wheeler). This is particularly possible with small family passenger cars (as opposed to a mini-van or SUV). Unfortunately, the height of the front of the car is insufficient to...... Similar Editorial : by jraynal. | Source : Auto Accident