How rust appears and how to prevent it - 303 Car Care

How rust appears and how to prevent it

Unfortunately, rust is a common problem that car owners face and it can be frustrating to deal with. Anyone who has owned a car (or bike even) will admit that seeing rust on metal work is a worrying issue. Most people know that dealing with it as soon as it is noticed is essential in preventing further damage.

Rust appears when metal is exposed to moisture and oxygen, which causes the metal to corrode and break down. This can happen to any part of the car's body, including the frame, doors, and undercarriage.

Below, we explore how rust appears on a car and how to prevent it from happening in the first place.

What is rust?

Simply put, rust is a type of corrosion that occurs on metal surfaces when they are exposed to oxygen and moisture. The scientific name for rust is iron oxide, and it is typically reddish-brown in colour.

Rust forms when the iron in metal reacts with oxygen and water to form hydrated iron(III) oxide. It is a common problem for vehicles, machinery, and metal structures, and is a major concern in industries such as construction and manufacturing.

Why is rust a problem?

If water is allowed to enter imperceptible cracks in paintwork or metal, it works fast and the process of corrosion will begin. Salt can speed up this process further. Weakening metal and causing it to corrode over time, rust leads to structural damage if left untreated. Rust prevention is possible through proper maintenance and protective coatings, but once it has formed, it can be hazardous and requires immediate action to prevent further decay.

How does rust appear on a car?

As outlined above, rust appears on a car if the metal is exposed to moisture and oxygen. You might ask how this happens in the first place. We can identify the predominant ways rust occurs on cars as follow:

Salt and Chemicals

In areas where roads are frequently salted or treated with chemicals to prevent ice build-up, the salt and chemicals can accumulate on the car's undercarriage and cause rust. Salt can create tiny scratches to paintwork which can allow moisture to creep in.


When a car is routinely exposed to moisture, such as rain, snow, or condensation and not dried sufficiently on a regular basis, the moisture can seep into the car's bodywork which gives an opportunity for corrosion to begin.

Scratches and Dents

Large or small scratches and dents on a car's body can expose the metal to moisture and oxygen. Not treating scratches, dents or damage to bodywork or paint work quickly will undoubtedly lead to rusting.

What prevents rust on a car?

Rust prevention on a car is essential in maintaining the car's appearance and prolonging its lifespan. Luckily, there have been some pretty great technological advances in rust prevention over the past few decades that car manufacturers invest in heavily. But there are also some simple ways that car owners can protect their vehicles themselves as well as products that can help remove car rust.

Here are some helpful tips:

1. Wash your car regularly

Washing your car regularly can help remove salt, chemicals, and other contaminants that can cause rust. Using a car wash soap (such as Salt Neutralising Wash Boost) that is specifically designed to neutralise the harmful effects of salt is a great choice here.

2. Wax your car

Waxing your car creates a protective barrier that can help prevent moisture from reaching the metal. It can also help remove water spots and creates a protective layer to help repel dust and debris which can lead to scratches.

3. Fix scratches and dents

Fixing scratches and dents as soon as they happen can help prevent rust from forming. Using a rust inhibitor afterwards will help solidify your efforts here too but if you’re unsure on products for this, a good car detailer will be able to help.

4. Rust proof your car

Rustproofing your car involves applying a protective coating to the car's undercarriage and other areas prone to rust. You can easily invest in a rust stopper spray which will do this job for you, or take your car to a trusted car detailer who will provide advice or service the car themselves.

Store your car properly

If you live in an area with harsh winters or with a high volume of passing traffic, consider storing your car in a garage or covered area to protect it from the elements and flying debris or salt.

At 303 Car Care, we have a deep understanding about what causes damage to the interior and exterior of your car. 303 products are globally renowned and are designed to help protect and prolong the lifespan of your vehicle. If you have a car maintenance issue that you’re itching to get sorted, contact us and we can provide you with the expert advice you need.

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