Can you mix Red and Green Anti-freeze?

Anti-freeze is a concentrated chemical liquid that is made up of ethylene glycol and propylene glycol. Its main use is to lower the freezing point of coolants to prevent their freezing in the winter season and ultimately stops them from jamming the engine.

Most antifreeze also increase the boiling point of coolants to prevent boiling over and to ensure even operating temperature and smooth running of the engine.

When anti-freeze is diluted with water it is referred to as coolant. Coolant regulates the engine temperature by pulling away the heat produced in the engine and thus preventing it from over-heating.

There are 3 types of anti-freeze:

  • Inorganic Acid Formula (IAT)
  • Organic Acid Technology {OAT)
  • Hybrid Organic Acid Technology (HOAT)

What you need to know about Red Anti-freeze?

Red anti-freeze is produced with HOAT (Hybrid Organic Acid Technology) which is the combination of IAT (Inorganic Acid Formula) and OAT (Organic Acid Technology).

It is commercially termed as Dexcool. It is meant to be used for European, Japanese, and Asian vehicles like Honda. Hyundai, Nissan, and Toyota vehicles.

Red anti-freeze has a longer lifespan of almost four years.

The color of the coolant turns out pink when red anti-freeze is mixed with water.

What you should know about Green Anti-freeze?

Green anti-freeze is produced with IAT (Inorganic Acid Formula) which is one of the earliest technologies in anti-freeze manufacturing.

The base used in this case is either ethylene glycol or propylene glycol with additives like sulphates or phosphates.

It is meant for older vehicles that are pre-2000 generation because they contain a good amount of steel and copper parts in the cooling system and green anti-freeze has been proven effective against corrosion.

It also forms a thick protective layer which helps against leaks and cracks in the cooling system.

The lifespan of this anti-freeze is about three years after which it needs to be flushed out and changed with a fresh amount of anti-freeze.

Difference between Red and Green Anti-freeze

CharacteristicsRed Anti-freezeGreen Anti-freeze
Technology usedHOATIAT
TypeDevelopedOldest
Additives usedInorganic and organicInorganic
Vehicles to be used inEuropean, Japanese, and AsianPre-2000
ClassG12C11
AffordabilityRelatively expensiveCheaper
LifespanFour yearsThree years
Functioning PeriodLongShort
StabilityMore stableLess stable
EffectiveMoreLess

Can Red and Green Anti-freeze be mixed?

The simple answer is no. Mixing these anti-freezes can cause problems for the engine.

In fact, mixing any type of anti-freeze can cause problems because every vehicle comes with its own recommended anti-freeze which is best suited for its own functioning.

Vehicles may be used with other type of anti-freeze, but it is better to use the recommended coolant as using or mixing different types of anti-freeze might damage your vehicle and it is a costly mistake to make.

Why can Red and Green Anti-freeze not be mixed?

Mixing these anti-freezes will not cause issues like explosion but it will harm the vehicle.

Mixing red and green antifreeze can result in a thick gel which would no longer be able to flow through the vehicle’s cooling system.

This can overheat the cooling system and cause damage to its different parts.

The main reason these two anti-freezes cannot be mixed is that both of these are made from different technologies which use different types of additives.

Both anti-freezes have slightly different or added functions that might interfere with the others.

Moreover, both anti-freezes have different lifespan so one will wear out faster and quicker than the other.

If the red and the green anti-freeze is mixed, it can give inaccurate readings of the freezing point to the mechanic or if the mechanic checks to see if there is enough coolant within the vehicle, inaccurate data will throw off the estimate or calculations.

This is dangerous because if the temperature falls too much and there is not enough coolant than the engine might crack.

Therefore, it is better to be safe than sorry and try not to risk mixing anti-freeze and take advice from the mechanics to prevent a costly and unnecessary mistake.

What to do if you have mixed anti-freeze?

Get your vehicle checked to a car mechanic.

If you are fortunate, they will catch your mistake in time, and you will only be required to flush out the mixed anti-freeze that is causing the problem and switch it with the anti-freeze that is recommended for your vehicle.

If unfortunate, then your car will need more work and fixing.

This may include repairing or replacing components of the cooling system or even the engine or its damaged parts.