Why is anti-freeze so important for your vehicle

car anti-freeze
car anti-freeze

Why anti-freeze is so important for your vehicle

As we head into winter and the temperatures drop below freezing you’ll need to start thinking about how to keep your car running throughout the colder months. One think you’ll need to check is your anti-freeze. Here’s some information for anyone who’s ever wondered what it does and why it’s so important for your vehicle throughout the year.

What is anti-freeze?

Anti-freeze is a coloured liquid that stops the water in your engine’s cooling system from freezing during the winter months. It does this by lowering the freezing point of the water. As the temperature outside drops, coolant is pumped throughout your engine block to maintain an even temperature. 

It’s supplied as a concentrated liquid and needs to be diluted before use. Engine coolant does the same job as anti-freeze but is ready to use and doesn’t require diluting.

Your vehicle needs anti-freeze throughout the year, not just during the winter. It helps to protect your engine from corrosion, aids heat transfer and prevents rust & scales from building up. In hot temperatures it prevents your engine from overheating by raising the boiling point of the water in the cooling system. 

Different vehicles require different types of anti-freeze so it’s important to check which is suitable for your vehicle before you use it. 

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Are anti-freeze and coolant the same thing?

There are multiple types of antifreeze available for our vehicles. Different formulations come in a variety of colours that range from green and blue to bright pink. Some are sold as concentrated forms, whilst others are ready mixed solutions. 

Anti-freeze and coolant are very similar and do the same job but have different concentrations.

  • Anti-freeze is concentrated and needs to be diluted with water before use.  This would often be around 50% concentrate with around 50% water.
  • Engine coolant is ready mixed and so can be used without the need to dilute.
anti-freeze in jug

How often should you check engine coolant?

Advice does vary slightly between vehicle manufacturers, but as a general rule it should be checked at least twice a year, before summer & winter. It should be topped up whenever the anti-freeze level drops below the guide marks or if you see a warning light on your dashboard.

  • Check at least twice a year
  • Before summer & winter
  • Whenever you see a coolant warning light
  • Antifreeze is checked during interim & full servicing

How to top up anti-freeze

Your vehicle’s anti-freeze reservoir should be easy to identify by its coloured lid which often has a warning symbol on the cap to highlight the danger of unscrewing the cap when the engine is running or hot. 

  • Check the type of anti-freeze is suitable for your vehicle
  • Ensure your car engine is cool
  • Check the minimum & maximum lines
  • Use a rag and/or protective gloves to remove the reservoir cap
  • Fill to the line recommended in your handbook
  • DO NOT overfill as this can lead to damage

When it comes to draining & replacing the anti-freeze altogether, advice varies depending on the vehicle manufacturer. It’s generally recommended to have an antifreeze change after around 30,000 miles. Take a look in your handbook for specific advice for your vehicle.

engine coolant reservoir

If you need help or advice on topping up your antifreeze please contact your local Eden Tyres & Servicing branch where the team will be happy to help.