6 Simple Reasons Why Modern Cars Do Not Rust (That Much)

One common thing with older cars is rust.

According to Christen Brownlee, classic cars keep shrinking and dropping like flies due to a well-known chemical reaction; rust.

It is not that modern cars don’t rust, but not as much as older ones, which may get you wondering.

As a whole, modern cars don’t rust because of the improvements in the manufacturing industry. There’s the use of lighter materials for production, galvanized steel, and much better quality paints.

The materials used don’t rust easily and are protected with more durable coatings that block rust and make the cars last longer.

Modern cars are lighter than older cars, with none of those heavy metals that are vulnerable to rust.

In fact, new cars are your best bet if you don’t want to deal with rust much during your vehicle’s lifespan or while you own it.

But how sure are you that they don’t rust?

Why Do Modern Cars Not Rust?

The truth is, modern cars hardly get rusted. If you drive one, you likely wouldn’t have to treat rust throughout the period you own it.

But, of course, how you care for the car also matters. The fact stays that corrosion and rust aren’t problems you would worry about with modern cars.

Why?

In total, modern cars do not rust due to the following reasons:

  • Better paint jobs
  • Improved lubricants
  • Galvanized steel
  • Cars are more watertight
  • Undercarriage coating
  • Aluminum parts

Generally, the reason modern cars don’t rust is because of the improved materials that go into producing them.

Here’s how they are better:

Better Paint Jobs

Paint plays a major role in preventing rust on cars. It is a protective layer that prevents moisture and air from penetrating the car’s body.

Once you solve that, you’ve solved a large percentage of what causes car rust. 

With the recent, more improved way of painting modern cars, they don’t rust as fast as older cars.

Many manufacturers paint modern cars with primers and sealers before applying the final painting to the car’s body.

This will reduce the contact between the oxygen in the air and the car’s metal body. 

In addition, manufacturers use quality paints on cars.

These newer quality paints contain chemical additives that create a shield on the car that serves as rust prevention and prevents moisture from reaching the metal.

Furthermore, they coat other vulnerable parts of the car with anti-corrosion waxes to protect them from rust. 

Improved Lubricants

Beyond a car’s body, there are other car parts that rust and are somewhat invisible.

These are the inner parts of the car. Modern lubricants do a better job of protecting sensitive car parts from rust.

They offer superior protection against harmful chemical attacks from corrosive elements and oxygen in the air.

Newer car metal parts are very much cleaner than older cars. Back then, petrol engine fumes had gaseous hydrocarbons that emanated from unburnt fuel, causing harm to car parts.

However, modern cars now use catalytic converters, which are much better.

In the past, petrol engine combustion was high in sulfur, phosphorus, and nitrogen, and they caused more rust problems for the car’s chassis and other rusted areas.

However, the modern lubricants and paints used on newer cars are more scratch-resistant, thin-layered, and ultimately protect modern cars from rust or delay rust from happening too quickly. 

Galvanized Steel

Another reason modern cars don’t rust is because of the galvanized steel used in producing them.

Manufacturers started using galvanized steel in car production in the 1980s, and the results have been satisfactory. 

Galvanized steel is usually coated on both ends with rust-resistant zinc. The zinc on the exterior of both ends is usually chemically attached to the iron body of the car, composing the steel. 

Generally, if this type of steel is well cared for, it can last up to 70 years, with the coatings protecting it.

The zinc coating comes in direct contact with the oxygen in the air, protects the alloy underneath, and ultimately stops corrosion from building on modern cars.

However, this layer wears off with time, but they would have protected the car a great deal.

It will protect the metal from water and chlorine, but rust may creep in once the zinc coating washes off and the metal is exposed.

This often occurs in areas with much salt or water on the road.

The salt will speed up corrosion and, ultimately, rust, which is why it is important that you clean your car often to prevent it from clinging to your car for too long.

Cars Are More Watertight

Some parts in older cars that were more prone to rust were the sills and wings.

This is due to the body panel designs. These areas can collect water and salt that can build up to become rust.

Salt and water accumulate in the body panels after driving them around; and when neglected, they can become a problem.

However, newer car models attach different car sections using bolts instead of rivets. 

This reduces salt and water penetration into the metal sheets. They are more watertight, preventing water from penetrating and clinging to the area.

Furthermore, the newer designs of cars’ inner wings ensure that the water slides off the car instead of accumulating on it.

Manufacturers also reduce areas where mud can gather on cars by using fewer seams. More so, they sometimes use plastic instead of metal for areas prone to rust.

Undercarriage Coating

Another thing that makes modern cars not rust is the undercarriage coating.

The undercarriage is more prone to rust than the other car parts. It is closer to the ground and more likely to collect dust, water, and debris.

Coupled with that is that they are hidden, therefore, easily neglected.

The only way to protect it is to ensure a barrier covers the place. 

Modern car manufacturers always add extra coating on the undercarriage to protect water from penetrating the metal.

This protects the undercarriage from rust for a longer period.

Aluminum Parts

Aluminum is very popular because it is rust-resistant, which is why it is one of the materials manufacturers use to make their cars.

It is much lighter than steel and may help improve a car’s mileage a great deal. 

Due to its lightweight and rust-resistance reputation, manufacturers use it to make some car parts.

However, they are not as rust-resistant as galvanized steel and can corrode due to circumstances.  

Do Older Cars Rust More Than Newer Cars? 

Whether older cars rust more than newer cars has been something of wonder.

The truth is that all cars rust; however, the rate at which they do is different.

Some cars are more rust-prone than others, leaving the question as to whether older cars rust more.

Generally, older cars rust more than newer cars due to the material used in producing them, and they don’t have as many layers of protection as modern cars do. The reasons older cars rust more than newer ones are due to:

  • Steel body
  • Inferior painting
  • Car design
  • Rust-prone seams

Before the auto industry experienced some developments, the older cars produced were rust-prone.

This makes the major reason why older cars are more rust-prone is the absence of development explained as:

Steel Body

In the past, older cars used steel bodies. This body, as compared to galvanized steel, isn’t coated, making it bare and vulnerable to rust.

The steel used is usually heavy metal that rusts quickly, and often, the paint coating covering the body doesn’t help much to protect it from rust.

Inferior Painting

Another reason older cars rust faster than modern ones is due to inferior painting. The paints available then and now are different. 

Newer paints have chemical additives that can inhibit paint. Another thing is that older cars didn’t have layers of primer and sealer to protect the vulnerable metal before the final paint covering.

Car Design

The design of older cars was another problem that made them rust faster.

Back then, car design and technology were still evolving, so many cars had crevasses and small pockets that collected mud that eventually gave room for rust to appear.

In addition, car wing parts were not as improved as they are now and allowed moisture to cling to some hidden parts.

Rust-prone Seams

Older cars have rust-prone seams. In the past, the seams used to be metal.

Additionally, the seams were many, and they often tend to be the first corrosion spots on cars.

However, newer cars use plastic instead, making them rust-resistant. Manufacturers also use fewer seams on cars now to prevent corrosion.

Final Thoughts

As you’d have known by now, rusts are one of the things you might have to deal with if you have a car.

But how much rust you will deal with and how often depends on the car you’re driving and how well you care for them. 

You are lucky if your car is modern because they don’t rust like older cars.

Nevertheless, all cars are prone to rust, whether modern or old; however, proper care and maintenance can do the trick of protecting your car.

Key Takeaways:

  • All cars are rust-prone
  • Older cars rust more than modern cars
  • Improved materials and development in the auto industry prevents newer cars from rusting quickly
  • Modern cars use lightweight metal

References

https://dasilvaautobody.com/blog/auto-body-repair/older-cars-rust/

https://totallossgap.co.uk/blog/post/why-do-modern-cars-not-rust/560#:~:text=Modern%20cars%20are%20made%20of,they%20simply%20do%20not%20rust.

https://autoexpert.com.au/posts/why-dont-cars-rust-as-badly-as-they-used-to

https://www.munstertyresandservicing.co.uk/news/why-dont-cars-get-rusty-anymore/

https://www.wapcar.my/collect-faqs/honda-cr-v-undercoating-1656041634481

https://www.askthecarexpert.com/car-rust/

https://www.quora.com/Do-modern-cars-suffer-from-rust

https://www.askthecarexpert.com/car-rust/#:~:text=Actually%20cars%20do%20rust%E2%80%A6&text=That%20protective%20layer%20of%20zinc,in%20all%20sorts%20of%20places.

https://www.quora.com/Why-were-cars-in-the-70s-and-80s-so-much-more-prone-to-rust

https://www.acs.org/content/dam/acsorg/education/resources/highschool/chemmatters/articlesbytopic/oxidationandreduction/chemmatters-feb2006-flaking-away.pdf 

Jan-Lucas Ganssauge
Jan-Lucas Ganssauge