No matter how well you maintain your vehicle, rust can develop. If you have a mysterious leak or your paint is damaged by road debris, scratches, or dents, rust is inevitable. In many cases, the automotive parts you purchase may not have any zinc or coating to seal out the corrosive reaction. Corrosion develops because your vehicle is both an anode and a cathode. All it requires is an electrolyte to start the oxidation process. Water is an electrolyte but is not very good at transferring electrons without salt.
Before the galvanization of the automotive frames in the 80s, cars were virtually disposable. This is the reason why a limited number of classic cars have survived, and the best examples come from the deep south. Galvanization involves coating the steel with a zinc coating to inhibit oxidation. It is less effective in cold temperatures, however, and only slows down the oxidation process.
You must work quickly to repair your paint when it is damaged by using touch-up paint to seal any scratches. If you wait, it is only a matter of time before the corrosion process begins. And once it starts, it does not stop. Auto body shops are unable to provide a warranty on rust repairs. This is because it affects the vehicle at a molecular level and may be impractical to fully contain. The rust can always come back because there are seeds for it to spread as environmental factors permit.
Undercoating and Sealants
There are different types of undercoatings for the undercarriage of vehicles that help protect them against the high-wear areas where rust commonly starts. Asphalt is one of the most durable coatings. However, it is not possible to protect surfaces that reach high-temperatures with asphalt. Sealants that repel water can be applied to exhaust parts, engine parts, and areas where water may well up. Applying paint protection films like the invisible car bra or fender flares can also help reduce rust.
Every owner should do the bare minimum of purchasing the rubberized undercoating sold in aerosol cans. If you have a car jack and an automatic car wash nearby, you’re set. Simply wash your vehicle and choose the undercarriage cycle. After it dries, you jack up the vehicle and spray on the rubberized undercoating. You will likely need several cans to obtain sufficient coverage. You can apply your sealant to the exhaust and other mechanical parts at the same time. The sealant application process must be repeated from time to time but provides an opportunity to inspect for corrosion.