"Frame damage" is a term that most people have heard, but it's also surprisingly antiquated. You'll often hear about frame damage following a severe accident, or you may even come across it when looking at a vehicle's VIN history. However, frame damage can be inaccurate when describing the effects of a collision on a modern vehicle. 

This inaccuracy comes down to the underlying difference in the structural design of modern vehicles. You can better understand why this matter by learning about the history and evolution of automotive structural design.

Body On Frame vs. Unibody

If you drive a modern vehicle that's not a pickup truck, there's a good chance you're driving a vehicle with a unibody structure. Trucks, heavy-duty commercial vehicles, and older cars use a body-on-frame design. This design includes a ladder-shaped frame that's separate and modular from the body, which is essentially a shell that sits on top of the frame.

The term "frame damage" derives from this design. Since the shell was essentially a cosmetic piece sitting on top of a more rigid structure, any damage to the body typically wouldn't affect the vehicle's drivability. On the other hand, frame damage could cause issues with alignment, tire wear, handling, steering, etc.

Unibody vehicles use an entirely different design. Instead of a separate body and frame, a unibody vehicle uses an underlying structure that runs throughout the entirety of the car. This design is lower-cost, lighter, and generally performs better than body-on-frame, but it also means that nearly any impact can affect the vehicle's structure.

Structural Damage Explained

While many people refer to frame damage when discussing unibody vehicles, structural damage is a more accurate term. An impact can cause parts of the underlying unibody "skeleton" to deform. This skeleton includes everything from the pillars on the side of the car to the rear quarter panels and hood rails.

Damage to this structure can impact your vehicle's performance or make it unsafe to drive. If parts of the unibody skeleton fall out of alignment, they can do everything from preventing your car from driving straight to causing your tires to wear themselves out rapidly. As a result, driving a unibody vehicle with structural damage is rarely a good idea.

Fortunately, an experienced auto body repair shop can deal with most structural damage to unibody vehicles. These shops use sophisticated equipment to measure the alignment of your vehicle's structure, allowing technicians to pull the unibody skeleton back into shape. Once restored to factory specifications, your vehicle will be safe to drive and perform as it did before your collision.

Reach out to a company like Elite Auto Collision to learn more.