Which type of vehicle construction uses a frame only in areas requiring extra support and a strong attachment point?

Semi-unitized stub rail construction refers to a type of vehicle design where a frame is utilized only in specific areas that demand increased support and robust attachment points. This allows for a lighter overall construction while maintaining strength where it is most needed, often in the front and rear sections of the vehicle.

This construction style is advantageous because it combines aspects of both unibody and full-frame designs, offering the rigidity of a frame while minimizing weight. By strategically placing the frame only in areas requiring extra strength, vehicles can benefit from improved fuel efficiency and performance without sacrificing safety and durability.

In contrast, unibody construction integrates the body and frame into a single unit, and full frame construction involves a complete frame under the vehicle, which can add significant weight. Monocoque designs feature a structural shell that provides support without a separate frame, further distinguishing it from semi-unitized stub rail constructions.