Two basic methods are used to construct most vehicles in the United States. The first is frame on body, and the second is uniframe or unibody. Collision damage will be different from one frame to the other.
Uniframe construction means the frame and the body of the vehicle function as one solid piece. This type of vehicle is intended to withstand only one collision. A frame and body construction means the body of the vehicle is a separate entity that has been welded onto the frame. This type of construction is meant to withstand multiple collisions.
Collision deferment in uniframe construction is based on a series of crush zones. The zones will bend or crush into the vehicle to minimize damage to the passengers. These crush zones can be used once. Damage to the uniframe is difficult to assess without the aid of a mechanic since it can always be more extensive than it appears.
Uniframe construction vehicles are designed to take the brunt of any collision so the occupant will be safer. Typically, once the frame has been significantly damaged, the car is totaled. In some cases, vehicles that have sustained even moderate uniframe damage may no longer provide the same level of safety an undamaged vehicle would.
