Over the last four decades or so, several developments in body panel engineering have made a huge difference to the corrosion resistance of vehicles.

The latest materials, pre-treatment technology and body construction combine to produce cars that no longer deteriorate into rust heaps over time, even if subjected to the elements.

Steel, which is an iron-based alloy and the most common material used in car construction, has been through various stages of development. This has resulted in steel alloys that are highly resistant to corrosion, in addition to increased strength.

The latest paints and painting technology have contributed to the quality of the finished bodywork. But it is the modern surface pre-treatment methodology in electro-galvanising and electrophoretic applications that have had a far more significant effect in achieving the best base coat of the raw steel panels, further enhancing rust prevention.

Additionally, body design engineers use non-metals such as polycarbonates, polyurethanes, thermos-plastics and carbon fibre-reinforced plastics to substitute for steel and even aluminium on various parts of a car body. Besides being lightweight and easy to manufacture, these materials are totally immune to rust.

Another aspect engineers pay particular attention to is ensuring that there are no parts of the car’s chassis or body that can potentially hold water or mud, and become difficult to clean out.

Owners of classic cars will know what this means. In many old cars, the doors, ventilation inlets and rocker panels are accessible to rainwater. When the drain holes are choked, rust forms from the inside.

Additional rust-proofing on a new car today is not essential because of all the modern materials and technologies mentioned above. However, in the event of an accident where a body panel is repaired instead of replaced, proper surface finishing is important to maintain the corrosion protection.

While the original steel surface is undeniably of the best quality available today, a compatible surface primer and finish coatings are essen...