Which construction is described as having no formal frame and where the body and frame are one piece?

• A. Unibody Construction
• B. Space frame
• C. Body over frame
• D. Ladder frame

Answer: (A)

Unibody construction is when the body and the frame are one integrated structure. There isn’t a separate frame carrying the vehicle’s load; the body itself provides the chassis and carries stresses, supports the suspension, and guides crash energy through the structure. This design is common in most modern passenger cars because it’s lighter, more space-efficient, and lets the entire shell work together to improve rigidity and safety.

In other constructions, the frame and body are distinct. A space frame relies on a tubular frame that the body attaches to, rather than being the body itself. A ladder frame uses two long rails with crossmembers, with the body mounted on top. Body over frame places the body on a separate frame that’s not integrated into the shell.