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

G12 is a type of coolant with red or pink color that is based on ethylene glycol and carboxylate compounds, it does not contain silicates and is used on cars from 1996 to 2001. Its service life is 4-5 years, and the density is 1.065 – 1.085 g / cm3 (at 20 ° C or 68 ° F). The freezing point is within 50 degrees C below zero or -58 ° F, and the boiling point is about + 118 ° C (about 245 ° F) and has in its component 2 or more carboxylic acids.

Because of its additives, G12 coolant inside the radiator, corrosion localization occurs only where necessary, forming resistant microfilm, it affects the formed foci of corrosion.

Often the percentage of ethylene glycol in the coolant is about 50% to 60% which allows for achieving the best performance. In its pure form, ethylene glycol is a colorless and viscous oily liquid that boils at 197°C (386.6 °F) and freezes at a temperature of -13 °C (8.6 °F).

Additives are added such as a dye to have greater visibility in the tank for a better advantage.

What does G12 coolant contain?

G12 coolant contains about 5% distilled water, ethylene glycol alcohol to prevent freezing, a colorant that is used often to distinguish the class of coolant but also to have better visibility in the reservoir.

Other additives that help especially because ethylene glycol is aggressive for non-ferrous metals, other additives based on organic acids that act as an inhibitor, and other substances that help against corrosion or to prevent the formation of scale

In addition to these additives, G12 coolant type must also have anti-foaming and lubricants.

A disadvantage of G12 coolant

G12 coolant has a big disadvantage, it begins to act only when corrosion appeared. Although this action prevents the forming of a protective layer and its rapid shedding as a result of vibrations and temperature changes, which makes it possible to improve heat transfer and longer use time.

G12 coolant vs G11, G12+, and G13

The three types of coolant classes, G11, G12 and G13 differ in the types of additives there are used: organic or inorganic

Differences between G12 and G11 coolant

The G11 coolant is an older coolant class. This one was used on cars manufactured before 1996 with a large volume of the cooling system. G11 is often blue or green. Its boiling point is 105 ° C (221 ° F) and it does not last more than 2 years or 31.000 – 50.000 miles.

G11 contains a small set of inorganic additives, phosphate, and nitrates, and was created using silicate, which covers the inner surface of the system with a protective layer, regardless of the presence of corrosion areas.

Although the G11 coolant protects already existing corrosion from damage, this coolant class has low stability, poor heat transfer, and short service life. After is worn out, the G11 coolant becomes abrasive and can damage the cooling system elements.

Unlike the G12 coolant, G11 is not suitable for cars that have aluminum radiators, because its additives cannot adequately protect this metal at high temperatures.

Mixing G12 coolant with G11 coolant

You should not absolutely under no circumstances mix an organic coolant with an inorganic coolant.

Differences between G12 and G12 + coolant

G12 and G12 + are both a class of organic “long life” coolants, they are both used in cars manufactured since 1996, and they both use ethylene glycol, but only G12 + is using a hybrid production technology in which silicate is combined with carboxylate technology.

In 2008 the G12 ++ coolant appeared. This coolant has a combination of organic additives and a small number of mineral additives, thus organic and inorganic additives were mixed. This combination made it possible to eliminate the main drawback of G12, not only to eliminate corrosion when it has already appeared but also to perform a preventive action.

Mixing G12 + coolant with G12 and G11 coolant

Although it is “possible” to mix G12 + with G12 and G11, I do not recommend that mix.

Differences between G12 and G13 coolant

The G13 is the newer coolant class that has been made since 2012, because of increasing environmental standards. Tho most common colors of this coolant are light red or violet. The freezing point of this coolant in its final form is -69° C (-92 ° F) and its boiling point are about 175° C (347° F) which obviously has the best cooling and antifreeze performances.

Unlike the G12, the G13 coolant class does not differ that much, the only differences are that G13 has in its composition propylene glycol, which is less toxic, and does less harm to the environment when it is disposed of (about 11% less CO2 emissions than G12), and its price is much higher than G12 antifreeze, and G13 is also excellent for cooling and protection against corrosion and chalk deposits.

G13 has higher protection for cars that have aluminum radiators but also cast iron and magnesium alloy material.

On the other hand, G13 coolant is not recommended to be used on older cooling systems that have copper or brass radiators and heaters. G11 and G12 are the best options for these materials.

How to choose the best coolant type for your car

When talking about choosing the best coolant, we should be talking first of all, about choosing the correct coolant type or class.

This is actually easy because valuable information about the right type of coolant is found on some car brands written on the reservoir tank, and for all car models, in the car manual.

Coolant comes in two forms, already diluted and fully concentrated. My advice is to buy the concentrated coolant and mix it with distilled water according to the climatic conditions in your area. If it’s colder, the coolant will have to be more concentrated, if it’s hotter it will have to be less.

When you choose the coolant, if you have a copper or brass radiator with a cast-iron block, then you need a green or blue G11 coolant. On a more modern car with an aluminum radiator, orange, purple or red G12, and G12 + coolant.

When buying the coolant, see if:

  • there is no pungent smell;
  • there are no sediments in the bottom;
  • the packaging was high quality without label errors;
  • price is according to what products are in the market;

Changing the coolant in your car

When changing the coolant, pay close attention to the car’s technical characteristics, you should find valuable information in your car’s manual

You need to remove the old coolant completely, wait for a complete drain of the old coolant and pour in the new coolant, and monitor it from time to time. If the coolant has changed its color then that represents a problem because the coolant is losing its protective properties and you should change it.

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