A Car-ful Passion

Understanding Auto Body Rust And Its Danger For Your Classic Truck

If you own an older truck you like to drive for special occasions, then you need to routinely inspect the body for rust damage. By catching rust when it first forms, you can have the damaged area of your truck fixed before the rust spreads and causes more extensive damage.

Understanding Auto Body Rust

Your truck is made from a steel alloy metal. This steel is very strong and resistant to rust. However, over time, oxygen continually comes into contact with the steel and will eventually react with the iron molecules in the steel and cause rust to form. The formation of rust is a permanent chemical reaction known as oxidation.

Once steel has become oxidized, the newly rusted areas no longer offer any protection to surrounding iron molecules. This causes the rust to quickly spread, and the areas of rust on your truck will grow exponentially larger over a short period of time. 

Fixing Auto Body Rust

The only way to fix auto body rust is to completely remove the damaged steel and either patch the area or replace the metal itself. To patch the area, your auto body shop will use a bonding product. The bonding agent is built up on the surface and then sanded and painted. However, if the area is very large, such as floorboard areas, then the steel is sometimes cut out and a new piece welded into place.

It is vital that the rust be 100% removed because if it isn't then the steel is open to oxidation and the area will just continue to rust after it is repaired. Simply painting over the rusting area will not solve the problem, as the metal will still rust from below.

Preventing Auto Body Rust

In addition to removing rust, your local auto body shop can also apply an undercarriage clear coating material. The purpose of this clear coat layer is to prevent oxygen from gaining access to your truck's metal. By stopping the access, you can prevent rust from ever happening at all.


By understanding how rust can eat its way through your old truck's steel, you are better prepared to catch it when it first starts to form. By having rust removed early, you can prevent much worse damage from happening to your truck's metal frame.

If you have any further questions about auto body rusting or collision repair, you should contact a local auto body and collision repair shop for more information.