Is Coolant Clear? The Antifreeze Color Details

The color of a coolant tells a lot about its properties. Clear coolants are used previously; they are just coolants made from glycol and water.

Although most antifreezes come in varied colors, it is rare to see clear or transparent coolants. Clear coolants were once dominant before colored ones were introduced to the market. Here, you will get the answer of your question, is coolant clear?

is coolant clear

Is Coolant Clear?

Coolants are meant to either be clear or have bright transparent colors. Once they stop being clear and start having inconsistent colors, it is a sign that it needs to be changed.

Coolants come in majorly 6 colors, and these colors are bright and clear. The colors include bright green, orange, red, pink, purple, and blue. Each of these colors represents a type of antifreeze.

Initially, antifreezes used to be just clear liquid, but in modern times the use of colored coolants is dominant.

Majorly the coolant color is used to differentiate between light-duty and heavy-duty engine coolants.

The diverse color antifreezes come with additives that help prevent corrosion and make them safer.

Clear coolants do not have that many additives compared to colored ones. 

The coolant’s color also makes it relatively easy to track down leaks in its pipes or reservoir.

When you discover that the radiator fluid you have is clear or transparent, please do not panic; it is alright; it shows that it is suitable for use.  

Why Is My Coolant Clear?

When you have a clear coolant, it shows that you use an Ethylene glycol-based coolant. This coolant is colorless and odorless, just like water. However, it does not mean that the fluid is terrible but do not use water as coolant.

The transparent coolant is mainly used during the winter period. It helps protect the engine from freezing up during the winter.

It also functions well in the summer, as it has excellent heat-collecting properties, preventing your engine from overheating during hot driving conditions.

Clear Antifreeze Properties

A clear antifreeze coolant is made of water and propylene glycol properties with some other additive to help protect the engine from corrosion.

With a clear antifreeze, you can see the level in the radiator, which will help you spot a leak easily.

Clear antifreeze has excellent properties that make it stand out among other kinds. They include the following.

  1. Reduced foaming
  2. Does not cause damage to internal parts
  3. Protects parts against deposits
  4. Great heat reduction property
  5. Neutral effect on internal parts
  6. Increased temperature protection

Clear or transparent antifreeze costs more compared to the colored types of antifreeze.

Coolant Colors

Different color coolants YouTube

Coolants come in different colors, which tells what type of fluid it is. There are four main types of coolants available in the market today. They include the following.

Organic Acid Technology

Organic coolants are primarily used with both heavy-duty and light-duty vehicles. In addition, it makes use of organic acid, which helps increase its usage.

Orange and red are their predominant color, but they can still be seen in yellow and blue. 

Inorganic  Acid Technology

This type of coolant is mainly used with light-duty vehicles. If you are using it with heavy-duty vehicles, it will require some additive to protect the engine parts from corrosion. Its primary color is light green.

Nitrite Acid Technology

Nitrite coolant, as the name implies, uses nitrite and other chemicals like molybdenum. You can find the fluid in red color.

Hybrid Organic Acid Technology

Finally, the hybrid coolant is a mixture of Organic and inorganic acid technology coolants.

The combination is done to provide a better fight against corrosion and rust. It comes in pink, purple, or blue.

If you notice well, most antifreezes come in the same color, making it harder to determine the type of coolant through their colors. Therefore, it is best to check the instruction to be sure.

Industry-standard manufacturers produce various brands of coolants, each with a specific color, typically orange for Organic Acid Technology (OAT) coolants, commonly used in modern vehicles for their extended service life. The orange coolant in a Jeep Wrangler’s radiator suggests a formulation to protect against high temperatures, corrosion, and engine failures.

Coolant colors aren’t just for show; they indicate different coolant formulations and technologies, such as Inorganic Acid Technology (IAT) or Hybrid Organic Acid Technology (HOAT), each with unique additives like SCAs (Supplemental Coolant Additives) for various system performance requirements.

It is vital for anyone maintaining their vehicle to use the correct concentration, typically a 50% mix of glycol and water, to ensure optimal cooling system performance and avoid costly engine damage. Color also indicates the condition of the coolant. Such as, for Jeep Wrangler owners and consumers alike, the color of engine coolant is a significant sign of the type and condition of the cooling system’s fluid.

What Happens If I Don’t Dilute Coolant?

Running your engine on pure antifreeze can be dangerous to your engine. Diluting the coolant with water has a lot of advantages. The freezing temperature of a pure antifreeze is around 0 to minus 5 degrees Fahrenheit.

When you mix it with water, the temperature comes down to a level where it can be used by the vehicle. It is why manufacturers give a certain percentage of the dilute mixture before you can use the radiator fluid.

Also, mixing the antifreeze with water can help increase its ability to collect heat from various engine parts during circulation.

When you use pure antifreeze, the engine system will lose a significant amount of its ability to transfer heat.

In addition, the water mixture helps to keep other additives active. When there is no water in the coolant, the additives will settle and may not be able to perform their functions. 

What Happens If You Run 100% Coolant?

Running your engine on pure coolants is not dangerous, but running it on pure antifreeze is hazardous to your engine.

It is essential to know that antifreeze and coolants are different. Antifreeze is a high concentration of glycol-based liquid that needs to be diluted before being used. When diluted, it becomes a radiator fluid, which your engine can use. You can also get a premixed engine coolant, which does not require dilution.

When pure antifreeze is applied to an engine, it is not as active as it should be, and the additive may not function, causing corrosion in the engine.

Keep in mind that antifreeze is flammable and also comes in high temperatures, which can cause severe problems for your engine. 

What Is The Best Mixture Of Coolant In A Car?

A standard antifreeze and water mixture ratio is between 50:50 and 60:40. The minimum mixture ratio is 70:30, and the maximum of 50:60. You mustn’t go above and beyond this requirement, as it can make the dilute less effective.

You can also consult your vehicle’s manual to get the exact mixture ratio that your engine will require.

color of radiator fluid


Coolants serve as an essential aspect of the proper functioning of the engine. It helps collect heat from various parts of the machine. Therefore, it is normal if you get a radiator fluid that appears clear or transparent rather than having colors. Hope the article has cleared your question, is coolant clear?

Transparent coolants are made significant from ethylene glycol and water, unlike other coolants that contain another additive like Propylene Glycol.

Akindayini Temiloluwa

I am Akindayini Temiloluwa, an automotive expert writer and car enthusiast. I have over three years of experience in the automotive writing niche and have completed over 300 pieces of content from 50 projects. I have vast knowledge and skill in vehicle repairing, all mechanical work, car upgrades and maintenance. My goal as an automotive content writer is to simplify the most challenging concepts for my readers, help them self-diagnose what may be wrong with their vehicles and offer real value for their time.

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