Oxidation: Iron’s Greatest Weakness

A car wash can do wonders for your vehicle's self-esteem, but it can also help protect your investment. Learn how to keep your car in one gleaming piece with Groupon's study of oxidation.

A tiny nick in a car's paint job is a little like a lit fuse on a stick of dynamite. Over time, both can blow a hole in the side of your car. Though a piece of exposed steel isn't as dramatic as a flaming fuse, both undergo oxygen-fueled chemical reactions. In the case of the chipped paint, the destructive culprit is oxidation, better known as rust. This reddish-brown compound is actually iron oxide, the product of iron's exposure to oxygen and water. (Since car frames are usually made of steel, an iron alloy, they’re naturally vulnerable.) If left to its own devices, oxidation will transform more and more of the metal into this much weaker substance, prone to crumbling and erosion. The addition of salt to the chemical equation—whether from seawater, road buildup, or an overzealous drive-thru attendant—only accelerates the process.

A simple coat of paint is enough to form a barrier between the car's frame and the invading moisture and oxygen of the surrounding environment, but little scrapes and scratches tend to befall even the most careful driver—and then there are all the parts beneath your car that don’t get the benefit of a paint job. The best way to thwart oxidation is to wash your car regularly, since even a thin layer of dirt can trap moisture close to the car's undercarriage and spur rust. Applying a coat of wax before the year's first snowfall will help protect the car's exterior, and a thorough rinse of the undercarriage in the spring will clear out any salty build-up and snowman eggs. Spring is also a good time to thoroughly clean your floor mats to thwart oxidation that might rot your ride from the inside out.