What is G12 coolant? | Differences between G11, G12, G12+, and G13 coolant

Published: 09/14/22 •  7 min read

Coolant cools a car’s engine. Coolants can be divided into four types today, with each type having its own additives and properties. Coolants available in stores are made up of water and ethylene, where the similarities end.

What is a Coolant?

g12 coolant-antifreeze

Coolant is the most common name for vehicle cooling fluid. Regardless of its classification, the coolant contains either propylene glycol or ethylene glycol and its additive package.

Ethylene glycol can be toxic. It is an oily liquid that tastes sweet. Its boiling point is around 200°,

and its freezing point at -12.5°. The lethal dose for humans of ethylene glycol is 300 g. The poison can be neutralized by ethyl alcohol.

Propylene glycol is an exciting new name in the coolant world. These coolants can be found in modern cars that meet strict toxicity standards. In addition to their excellent lubricating properties, propylene glycol-based coolant also has anti-corrosion and lubricating properties. It is made using light oil distillation.

Uses of Coolants

Its application has been limited to road transport. Coolant’s primary purpose is to maintain the engine’s operating temperature in a particular mode. The coolant is contained in the engine’s closed jacket and line. It also flows through the passenger compartment, where warm air blows when turned on. Some cars have a heat exchanger to control temperature. This is where oil and antifreeze intersect in the same case.

In cars, the main requirements are:

Several coolants can be used for this purpose: G11, G12, G12 +, and G13.

Also check: Does Coolant Affect the Air Conditioning?

What is G12 coolant?

G12 coolant has a red or pink hue and is based on carboxylate and ethylene glycol. Its lifespan is about 4-5 years, and its density is 1.065 and 1.085 mg/cm3 (at 20 degrees C or 68 degrees F). The freezing temperature is 50 °C below zero, or the temperature is -58° F. The temperature at which the liquid boils is approximately +118° C (about 245° F).

Due to the additives in G12 coolant, localizing corrosion takes place only in the required areas, forming resistant microfilms, which affect the corrosion foci. Moreover, additives are also added for better visibility in the tank.

In most cases, the proportion of ethylene glycol within the coolant can range from 50 to 60 %, which is enough to achieve the most efficient performance. In its purest form, the ethylene glycol color is a non-existent and viscous liquid that can be boiled at the temperature of 197° Celsius and can freeze at temperatures of 13°C (8.6° Fahrenheit).

Composition of G12 Coolant

G12 coolant has around 5% distilled water and ethylene glycol alcohol to stop the freezing process; a colorant is frequently used to identify the kind of coolant. It also helps improve the visibility of the reservoir.

Ethylene glycol is highly aggressive to non-ferrous metals, additional compounds based on organic acids that work as inhibitors, and other compounds that can help prevent cor

rosion or scale development. Alongside these additives, G12 coolant also contains anti-foaming agents and lubricants.

The Drawback of G12 Coolant

G12 coolant has one major disadvantage. It begins to work only after corrosion has begun to appear. However, this action does not allow the formation of an outer layer of protection. It prevents its rapid loss due to variations in temperature and vibrations that make it possible to enhance heat transfer and extend its use time.

G11 Vs. G12 Vs. G13

The three coolant classes, G11, G12, and G13, differ in the kinds of additives used.

G11 Vs. G12 Coolant

It is believed that the G11 coolant was a more traditional class of coolant. It was utilized in cars built prior to 1996 with an enormous amount of cooling system. G11 is usually either green or blue. Its boiling point is 105° Celsius and does not last for more than two years or 31,000 to 50,000 miles.

G11 is a set of inorganic ingredients: Nitrates and phosphate. It was developed using silicate, which coats the inside that protects the entire system regardless of corrosion zones.

G11 coolant helps to protect already damaged corrosion. It comes with low stability, inadequate heat transfer, and short serving time. When it wears out, the G11 coolant turns abrasive and may cause damage to elements of the cooling system.

In contrast to the G12 coolant, the G11 coolant isn’t appropriate for vehicles with aluminum radiators, as its additives cannot adequately protect the metal against high temperatures.

Mixing G12 coolant with G11 coolant – Mixing organic coolant with an inorganic cooling agent is not recommended.

G12 Vs. G12 + Coolant

G12 or G12 + are categories of organic “long life” coolants. They have both been utilized in automobiles manufactured since 1996. Both use ethylene glycol; however, G12 + utilizes the hybrid production method where silicate is used with carboxylate technology.

In 2008, the G12+ coolant was introduced. This coolant is made up of organic additives, as well as some mineral additives. Therefore, the organic and inorganic additives were combined. This mix allowed G12 to overcome its significant drawbacks of G12 and not just to prevent corrosion after it is already present but also to take preventative action.

G12 Vs. G13 Coolant

The G13 is the latest coolant class, developed in 2012 because of rising environmental standards. The most commonly used colors of the coolant are violet or light red. This coolant’s melting point in its most definitive version is -69°C, and its boiling point is around 175° Celsius, which is the most effective antifreeze and cooling properties.

Contrary to G12, the G13 coolant class doesn’t significantly differ from the G12 coolant class.

However, G13 coolant is not advised for use in older cooling systems with brass or copper radiators as well as heaters. G11 as well as G12 are the most suitable options for these materials.

Best Coolant for Your Car

When choosing a suitable coolant, it is best first to consider the appropriate coolant class or type for your car. It’s easy to do this since valuable information on the correct kind of coolant can be found on specific brand names of cars written in the tank reservoir and the car manual for all models of cars.

Coolant comes in two types that are already dilute and concentrated. WHEELSCRIBE suggests purchasing the concentrated coolant and mixing it with distilled water in accordance with your region’s climate. If it’s colder, the coolant needs greater concentration. However, if the temperature is higher, it will require a lower concentration.

If you have brass or copper radiators with a cast-iron block, it requires either blue or green G11 coolant. You will need an orange or red G12 coolant for a modern vehicle with an aluminum radiator.

Before buying a coolant, check if:

Changing the Coolant in Your Car

If you are changing coolant, be sure to pay focus on the car’s technical features. Make sure to check the details in the user manual of your vehicle.

It is necessary to take out all coolant from the previous one completely. Ensure complete drainage of the coolant before you put in the new coolant. It would be best to monitor it. If the coolant’s color has changed, this indicates that something is wrong since the coolant is losing its protection properties, and you need to replace it.


What does a coolant do?

Coolant is the cooling fluid for the engine. It has a high boiling temperature and is made up of water and additives to lubricate the pump as well as other CO elements.

What is the meaning of antifreeze?

Anti (against) Freeze (freeze). Antifreeze is the common name for antifreezing fluids found in cars.

What antifreeze are available in the market?

Ethylene glycol, hybrid ethylene glycol, carboxylated ethylene glycol, ethylene glycol, and propylene glycol. Antifreeze are also available in different colors, like red, green, and blue.