Servicing & Mechanical

What is the right coolant for your vehicle?

A vital element in your engines' operation


What coolant do I need?

You can find the right coolant and parts for your vehicle by using the My Garage tab at the top of this web page. All you need to do is punch in your rego and state or search by make, model and year. Once this is completed you will be suggested the right products to suit/fit your vehicle while searching our site.

When it comes to the coolant you must make sure that you’re using the right one. If you use the wrong coolant then over time you’ll begin to notice a drop in your car's performance, and can find a significant amount of damage. The most common method to find out is to simply check the coolant and find out what colour it is when the vehicle is cold. Most coolant brands will keep their coolants the same colour to prevent any confusion. If you're still not sure, check the owners/service manual for coolant specifications.

Ford Coolant

Can I use tap water as coolant?

If you choose to use only tap water in your cooling system, this can cause radiator, head gasket and thermostat corrision damage over time. But before that, you will find that water boils at 100c and freezes at 0c, this works outside the optimal range for engine requirements as some engines will heat up over 100c espesiliy on hot days. When water starts to boil, it'll build up pressure from the gas expansion in the system causing it to overheat the system and blow vital gaskets.

Types of coolant

What is coolant and why do I need it?

Coolant is commonly a liquid substance that is used in a closed system to reduce and regulate the temperature of an engine. The amount of heat generated by an engine is the equivalent of that required to heat a large house in winter in very cold climates! As engines and vehicles become smaller and more powerful they generate even more heat in a confined space, and aerodynamically efficient body designs tend to direct air away from, rather than into, the engine bay. When an engine stands idle in cold weather, water in the cooling system will expand as it freezes, and this can have sufficient force to crack the engine block or radiator.

Learn More: Signs that your coolant needs changing - Click Here.

Learn More: How to replace coolant - Click Here.

Learn More: How to check your coolant - Click Here.

An effective coolant must therefore:

  • Contain good heat transfer properties
  • Have a higher boiling point and lower freezing point than water
  • Prevent corrosion and erosion
  • Resist foaming
  • Be compatible with cooling system component materials
  • Be compatible with hard water
  • Resist sedimentation
  • Be as chemically stable as possible
VW Coolant

What is coolant made of? It's just water right?

Coolant is normally a concentrate fluid, usually made of Ethylene Glycol together with some protective additives that is mixed with demineralised water to produce coolant. Propylene Glycol, which is non-toxic, is sometimes used in the mixture, as well as, or even instead of, the more toxic Ethylene Glycol.

Glycol does not absorb heat as effectively as water, but when added to water it has the ability to lower the fluid’s freezing point as well as raise its boiling point. A common Glycol to water ratio used is 50:50. This will lower the freezing point of the fluid to minus 39°C and raise the boiling point to 108°C. Manufacturers can recommend other specific mixture ratios, but below 33.5% Glycol the coolant will give inadequate freeze protection, and above 65% Glycol the mixture has inadequate heat absorption.

What types of additives are used in coolants?

  • Conventional or inorganic additives
  • Organic additives
  • Hybrid mix of the two

A fully formulated coolant is comprised of a careful balance of ethylene or propylene glycol with rust inhibitors, corrosion inhibitors, scale inhibitors, pH buffers for the acid to alkaline balance, anti-foaming agents, and reserve alkalinity additives. Coolant should be changed at recommended intervals because some of the additives will age and deteriorate over time, reducing the effectiveness of the coolant. While some coolants are compatible with others, changing the chemical balance in the cooling system can affect coolant performance, so mixing different types of coolant is not recommended.

Penrite coolant

What are the different types of coolant? What is a coolant inhibitor?

When it comes to selecting a coolant, there are two things which you should take into account. First, you have to find what type of coolant you need. Second, you must find out what the base of the coolant is. First, the type of coolants, there are two main types of coolant, Type A and Type B.

Type A coolant contains an antifreeze + anti-boil component. This is typically either ethylene glycol and is used to decrease the coolant’s freezing point and raise its boiling point. A variety of different inhibitor packages are used in Type A coolants and depending on its application, different doses of glycol are used.

Type B coolant is a Coolant Inhibitor. It's similar to Type A coolant, and contains very small amounts of the additives that Type A (around 5-10%) does and is used more commonly as a rust or corrosion inhibitor and not as a “coolant.” This type of coolant was commonly used in vehicles before the 1980s.

The most common types of antifreeze which are used today include; Ethylene Glycol and Organic Acid Technology. When you’re out shopping for a coolant you’ll see a lot of different colours, but don’t let that scare you. Coolant is a transparent fluid and different manufacturers add dyes to differentiate the coolant base. Always remember to read your car’s owner manual before you add a coolant to the car. The most common colours you will come across are green, red, blue, yellow or orange.

  • Green coolant is your conventional coolant (Ethylene Glycol base) and is the most common type of coolant found.
  • Red coolant is typically has a base of Organic Acid Technology which has a different chemical makeup of green coolant and is designed to be suitable for aluminium radiators. Red coolant is often silicate and phosphate free for use in later Japanese and Euro vehicles.
  • Blue coolant is usually an Organic Acid Technology base and what makes it different from red coolant is that they’re normally Borate free which is a requirement for modern day Japanese vehicles that are supplied with blue coolant from factory.
  • Yellow or Orange coolants are the latest in technology and are normally a universal product. Some universal coolants will allow top up mixing to a certain percentage of the overall capacity of the cooling system, so it’s important to keep this in mind when topping up.

How long does coolant last?

Coolants typically contain something known as a “rust inhibitor” which is used to prevent components within the engine from rusting. This can lead to the coolant becoming flooded with contaminants which contribute to the deterioration of the anti-boiling and anti-freeze additives which are in the coolant. There are a few different factors to consider when determining how long coolant lasts and when it should be changed. The two main factors are the type of car that you drive and the quality of your cars current coolant. Many manufacturers suggest that you change the coolant every 3 years or every 75,000km, while others say that you can change the coolant every 200,000km. How often you change the coolant can also depend on how well you take care of your car and whether or not there are any underlying issues with it.

Can I mix different coolants?

Provided that the coolants which you are using have identical chemical makeup (for example, if two coolants are based on Ethylene Glycol), then it is normally safe for you to mix them together. If you aren’t certain on which base the current coolant that you have in your car uses, there are universal mixes available. If you don’t have access to a coolant then water may be used in place of it. However, it’s very important to keep in mind that water’s boiling point is significantly lower than a coolant’s and therefore, is less effective. Furthermore, coolants have rust-resistant properties whereas water does not.