Common causes of car corrosion are as follows:
road salt, dirt and moisture accumulating under the bottom of the car;
chips of paint or protective coatings with stones, gravel, minor chips and dents, leaving unprotected metal exposed to corrosion;
If you live in the region (country), where the vehicle is regularly exposed to corrosive factors, corrosion protection is particularly important. Some of the reasons for increased corrosion are chemicals used on the roads, sea air, and aggressive industrial emissions.
Moisture creates conditions for the most intensive development of corrosion. For example, the occurrence of corrosion is greatly accelerated by high humidity, especially at the freezing point of water. Under such conditions, corrosive materials come into contact with vehicle surfaces through poorly evaporating moisture.
Dirt is a typical cause of corrosion because it dries slowly and allows moisture to come into contact with the car. Even if the dirt appears dry, it can still contain moisture and contribute to corrosion. High temperatures can also contribute to corrosion of poorly ventilated parts of the vehicle where moisture can settle. For these reasons, it is very important to keep the car clean throughout the year, regularly removing dirt and accumulations of other materials from it. This applies not only to visible areas, but also to the bottom of the car.