Finder makes money from featured partners, but editorial opinions are our own. Advertiser Disclosure

Rusty cars are less safe in crashes

Those little orange spots could mean the structure of your car is disintegrating.

As a car ages, its components begin to rust and lose integrity, creating a safety hazard for the driver. Unfortunately, you can’t stop rust — but you can slow it down.

Rust causes weakness in cars

Engineers have found that rust causes metal to lose structural integrity and become weak, so an older vehicle doesn’t perform as it did when initially crash tested. This problem is further compounded when you consider that ageing models also feature fewer modern safety technologies.

Case study: Mazda 6 vs. Volkswagen Golf

Swedish nonprofit group Villaagarnas Riksforbund, along with an insurance company, conducted assessments on two different models of car dating from 2003 to 2008 that are known to have rust issues in critical areas — the Mazda 6 and the VW Golf.

The Mazda 6 did not perform well under the test.

During the Mazda 6 test, in a frontal impact collision, the crash test dummy’s head made contact with the steering wheel after the airbag bottomed out. The dummy then bounced off the wheel into the door.

The car’s body shell deformed in an unexpected manner and the floor caused lower leg injuries when spot welds failed and separated. Crash engineers noted that a weak floor could allow objects to pierce the vehicle’s underside and enter the cabin — with disastrous consequences.

The Golf, on the other hand, performed remarkably, losing only a single point from its original crash rating.

Winner: Volkswagen Golf

Researchers concluded that in a heavily corroded vehicle, occupants had a 20% higher likelihood of dying in a crash.

The VW Golf performed much better in the tests than the Mazda 6. This underlines a key finding of the study, that each car rusts in a unique and individual way due to a range of variables, making them unpredictable.

The laboratory tested both cars to the same standards the cars had when new, not to more recent and stringent evaluations.

How to identify rust problems

Manufacturers apply anti-corrosion paints to crucial components at the factory, but eventually chips and wear cause coatings to break down. Drivers living in coastal areas will suffer accelerated oxidation thanks to a high salt content in the air. Vehicles taken onto the beach also suffer badly with rusting.

You can identify rust by bubbling, flaky paint and a red/brown pitting. Rust generally starts small but will get worse if left untreated. If you’re buying a car, take time to look underneath and examine the condition of structural metal components. If you see ragged holes and lots of loose corrosion, the car may be too far gone.

It’s possible to use a hammer to ascertain the condition of metal surfaces. If you tap the steel and it produces a sharp, defined ring, the metal should be in sound condition. If tapping makes a dull thud, the steel has most likely started corroding.

Is it plastic or metal?

If you notice a new ding or scratch or see paint flaking from your car, you might not need to worry about rust. Many new cars have more plastic parts than metal parts. Your whole bumper might actually be plastic, not metal, so a rear end accident might not be cause for concern about rusting.

If you’re not sure, your mechanic can check for rusting potential and suggest options for protecting your car after your paint has been damaged.

How to prevent your car from rusting

Once the rust on a part reaches a certain point, it will need replacing or repairing by a professional welder. You are far better off preventing rust by taking some simple precautions.

  • If you drive in seawater or even on the beach, take time to wash your vehicle off with fresh water. This eliminates salt, which is a catalyst for oxidation. Clean the underside of your vehicle, too.
  • If you spot surface rust or light rust, abrade the surface to remove pitting and flakes, then paint over it with a corrosion inhibitor and anti-corrosion primer/top coat. Look for marine grade products, as these often perform the best.
  • Greasing nuts and bolts with a non-metallic lubricant can ward off rust and make removal easier. There are also anti-corrosion sprays available.
  • If you notice a window, door or seal is leaking, get it fixed right away. Moisture will make rusting worse.

Newer cars are safer

Research shows that newer vehicles are statistically safer. You can use our car loan comparison to find a great deal on a modern car.

Is your car covered in an accident? Compare car insurance

Name Product Gap insurance Homeowner discount Telematics Has an app? Available states
All 50 states
Your dedicated agent can help you find the best savings with multiple discounts and rewards programs.

Speak to an agent: 877-526-1527

loan/lease coverage
All 50 states & DC
Discover coverage that’s broader than competitors, valuable discounts up to 30% off and perks like shrinking deductibles that reward no claims.
Depends on provider
All 50 states
Get your most compatible insurance options via a "smart matching" method aimed at finding you value.

Compare up to 4 providers

Bottom line

If you’re driving a newer car, being proactive about rust can help you prolong its life. If your car is already nearly rusted through, upgrading to a newer, safer car could save your life in an accident, and the extra safety features could help you save on car insurance, too.

Frequently asked questions about cars rusting

Pictures: Shutterstock

More guides on Finder

Ask an Expert

You are about to post a question on

  • Do not enter personal information (eg. surname, phone number, bank details) as your question will be made public
  • is a financial comparison and information service, not a bank or product provider
  • We cannot provide you with personal advice or recommendations
  • Your answer might already be waiting – check previous questions below to see if yours has already been asked provides guides and information on a range of products and services. Because our content is not financial advice, we suggest talking with a professional before you make any decision.

By submitting your comment or question, you agree to our Privacy and Cookies Policy and Terms of Use.

Questions and responses on are not provided, paid for or otherwise endorsed by any bank or brand. These banks and brands are not responsible for ensuring that comments are answered or accurate.
Go to site