4 Main Reasons Some Cars Rust More Than Others (Explained)

Nobody likes to see their hard-earned money go to waste; this is the feeling you get when you see your car rusting. Rust just makes a car look terrible and gradually decreases its resale value.

Throughout the years, many new techniques have been employed to make rust a thing of the past. However, not all cars can altogether avoid the ugly occurrence.

In this article, we’re looking at some of the main reasons why some cars rust more than others.

Let’s jump straight in.

1. Neglecting To Maintain Your Car

As they say, prevention is better than cure, and this is the case when it comes to avoiding rust. You should not take a regular cleaning regimen lightly when it comes to avoiding rust on your vehicle.

Washing and car detailing are known to be some of the best ways to avoid rust. Regular cleaning habits such as waxing will also ensure that rust does not seep in prematurely.

One of the biggest culprits when it comes to car rusting is salt. Salt accelerates the rate at which metal rusts and this is especially true during the winter months.

Saltwater can seep into the underside of the car and slowly eats away the metal. Typically, you won’t see the gradual corrosion of the metal when it starts.

For preventive measures, a good jet washer will be able to penetrate hidden areas that you can’t easily see from the outside of the car. A regular jet-washing routine ensures that you clean these areas before the rust takes hold of the metal.

Areas such as the underside of the car, inside of the wheel arches, and behind the body are the weakest points. Focus on these areas during the cleaning process, especially with a jet washer.

Another issue is the areas of the car that hold water after a good cleaning or after it rains. Water often stays in these small areas and slowly seeps into the metal.

The corrosion process will likely begin in these hard-to-reach areas where you can’t easily dry them off. These might be behind the lights, under the sills, and even below the undertray.

While you can easily clean the area with a jet washer, the drying process is slow. This is when the metal is most susceptible and corrosion begins.

You’ll find that professional car cleaning services often have a vigorous drying process after cleaning. This is to avoid water staying in these areas for a long time and give the rusting process a chance.

To take things further, you can even ask your garage or mechanic to check your car’s drainage system. This is a channel where the flow of water moves out of the car.

If the drainage system is clogged or damaged, water can permanently stay in the system. This will eventually lead to corrosion as the water start penetrating the metal.

With that said, a good cleaning routine coupled with some drying and a little care can go a long way in protecting your car against rust. It will not completely prevent rusting but it will definitely slow it down significantly.

Read about what you should expect if you’re thinking whether all cars rust eventually.

2. Driving in Rainy Conditions

Salty moisture is a surefire way to get the corrosion process started in a car. You can expose your car to this either from salty air, rain, or snow.

Salty water that you might find in a coastal area is one of the leading causes of rust. Seawater areas are mostly humid and this can cause the oxidization process to start.

Note that the iron in the metal of the car is what reacts with the water and oxygen, and this reaction causes rust. Since you can’t completely avoid rain on your car, this reaction is bound to happen at some point.

Regular exposure to rain will result in an increased chance of rust formation in your car. To avoid this, a rigorous cleaning and drying routine is a must especially if you live and drive in rainy areas.

It gets worse if you live and drive in an area where there is constant sleet and snow. If the snowy road is treated with salt, it will eventually penetrate the metal in your car.

Mind you, salt is typically used to grit icy roads, and this means the corrosion process will be accelerated on your car.

Common areas where the rust forms are the exhaust, wheel wells, doors, and frame rails, among others. And these are where rain will most often penetrate. Make sure you also check out where cars rust the most in the U.S. here.

A good idea is to use specialized cleaning products or waxing for your car if you constantly drive in rainy areas. These act as a layer of protection and can make sure the body of the car does not absorb moisture.

However, a good car cleaning company will know what products to use in a particular area. They will also know which areas of the car need the most attention in order to avoid corrosion.

Another factor that could add to the accelerated corrosion is exposure to extreme temperatures or sunlight. Heat often speeds this process up by solidifying the oxidization process quickly.

Moreover, driving in potholes and puddles can also speed up the rusting process. This is often what happens when driving off the road.

It is, therefore, a good idea to get on a regular cleaning routine if you live in rainy areas. This will keep your car looking good and retain its resale value throughout the years.

Rain and salty water will eventually lead to a type of rust called scale rust. If you leave this kind of rust untreated, it will only degenerate into the worst form.

3. The Quality of the Steel Used

Modern cars go through an advanced galvanization process than old cars are used to. In this process, the steel is dipped in zinc and acts as a protective layer for the steel underneath.

In recent years, manufacturers use higher-quality steel for the bodywork of their cars. When good steel is coupled with galvanized steel, it has a better chance of avoiding corrosion over time.

In the production process, the steel itself will undergo multiple treatments before being installed into the bodywork design.

Pre-galvanization and protective layers are used before the metal is painted with the final color. Also, protective zinc and a variety of protective polymers are used in some of the most expensive cars in the world.

In an effort to curb corrosion even more, manufacturers now even started using materials other than steel. Plastic or aluminum is used in certain parts of cars because these materials don’t corrode. To ascertain this, check the 25 cars that rust the least here.

Mind you, the protective zinc layer does not last forever and will eventually wear thin over the years. Some corrosion will always seep in despite all these protective layers but we just can’t see it.

4. The Galvanizing Process Fails

The manufacturing process of a car is a very long and arduous process, and a lot can often go wrong. Machine or human error during the galvanizing process can leave the protective layer weak and unable to protect the metal.

When the galvanizing process fails, the metal is left exposed, and this will eventually lead to corrosion. It can also happen when the zinc layer is way too thin on the metal.

Smaller manufacturers also cut costs this way in order to make their cars more affordable. They’ll skimp on some of the protective layers in order to save money and this is why cheaper cars are susceptible to rust.

Machine error is also one of the causes of the possible misapplication of the zinc layer. A machine must be programmed correctly to ensure it covers the metal with zinc thoroughly.

In order to make sure the protective layer is applied thoroughly, an inspection is often done afterward. A human will be able to tell if the layer of protective paint covers the entire body of the metal.

Skimping on this process is what leads to premature rusting in modern cars. Thus, the process needs to be thorough to ensure the car can avoid rusting for a longer period.

With that said, modern metals do far better in terms of preventing rust damage than older cars. However, this does not mean that you can stop maintaining a regular cleaning and drying routine to protect your car.

One of the biggest factors behind modern cars rusting slower than older cars is the lighter alternative metals used. Plastics, carbon fiber, and aluminum go a long way when used instead of traditional metals.

Modern cars also don’t really need rustproofing treatment because it is already added at the factory level. Multiple layers of protection are already applied during the manufacturing of the car.

Meanwhile, some dealerships will claim that you need to pay extra for rustproofing treatment of a car. This is often just to make more money out of the sale of a car.

Meanwhile, here are some reasons some cars rust very little.

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