Home Cooling System Can You Mix Antifreeze? – Here’s What Professionals Recommend

Can You Mix Antifreeze? – Here’s What Professionals Recommend

by Kelvin Yates

In most cases, you might be tempted to mix two different types of antifreeze. And thus, this begs the question, ‘can you mix antifreeze?’ Read on to learn whether mixing different types of antifreeze is a good or bad choice for your vehicle!

Besides oil, a significant part of car maintenance involves taking care of fluids. A car has different essential fluids that are important for the efficient operation of the vehicle. Among them is the engine coolant/antifreeze, which prevents it from freezing. While these chemicals play an essential role in a car’s cooling system, they do break down and become less effective over time.

How frequent the antifreeze needs to be replaced will vary from vehicle to vehicle. However, the standard duration is every 30,000 miles or two years. So, can you mix antifreeze, just to make this maintenance easier? Well, let’s find out…

So, What Exactly Is A Car Antifreeze?

A car antifreeze or coolant is a colored liquid, particularly ethylene glycol, mixed with water. It plays several purposes in your car. As the name suggests, during winter, it stops the water from freezing. In summer, it helps dispel excessive heat from your car engine to avoid overheating.

Antifreeze also helps protect your car’s engine from corrosion and prevents rust and scales from building up. Dirt, rust, and other particles can clog your vehicle’s cooling system and cause problems.

What Makes A Good Antifreeze?

A good engine antifreeze keeps your vehicle’s engine from overheating and freezing. Besides, it also helps improve your car performance and protect the engine from corrosive elements. With that said, it’s crucial to have a glimpse of ingredients that make up a high-performing car antifreeze. This should also help us to understand more about can you mix antifreeze.

1) Water

Almost all engine antifreeze is made up of 50% water. A mixture of water and antifreeze creates a coolant. Most car owners opt for this DIY process, while some purchase an already mixed-up coolant.

Can you mix antifreeze

2) Ethylene glycol

Ethylene glycol is ideally known to be the most active ingredient in most antifreeze. This chemical was first used as an antifreeze ingredient following World War I. Ethylene glycol plays a significant role in your car’s cooling system in that it ensures the liquid circulating throughout your vehicle’s engine doesn’t evaporate in extreme heat and doesn’t freeze in extreme cold.

3) Propylene glycol

Instead of ethylene glycol, some engine antifreeze use propylene glycol, which is more viscose than ethylene glycol. This implies that ethylene glycol has a more efficient heat transfer. However, the fact that propylene glycol is considered less toxic has made it a central selling point for car owners with pets and children.

4) Corrosion Inhibitors

While water, ethylene glycol, and propylene glycol create the base of most antifreeze, different additives that prevent corrosion create various types of antifreeze. Corrosion inhibitors can, however, vary depending on where it’s manufactured. For instance, Asia-manufactured vehicles use phosphates and carboxylates as corrosion inhibitors in their engine coolant.

Antifreeze for cars manufactured in Asia cannot use silicates as a corrosion inhibitor. But European vehicles use carboxylates and silicates mixture in their coolants to protect against corrosion.

One corrosive inhibitor is not necessarily superior to the other. And, different ingredients exist to unravel various problems. For example, Asian-made vehicles often had issues with poor heat transfer. For this reason, engine antifreeze for these vehicles doesn’t use coolants with silicates and instead uses carboxylates and phosphates to fill the anti-corrosive role.

In Europe, coolants solve a different issue. Hard water containing magnesium and calcium reacted with phosphate inhibitors in coolant, forming scale on car engines. Therefore, car antifreeze for European-made cars does not contain phosphates. They use carboxylates and silicates instead.

Can You Mix Antifreeze?

Coolants come in several colors. Some car owners and mechanics believe they can just mix the different colors. Unless you’re an expert on various reaction types and the exact chemical composition, never mix different types of antifreeze/coolants. So, the answer to ‘can you mix antifreeze’ is a solid, no. Keep it simple and adhere to the manufacturer’s recommendations.

Mixing antifreeze is a huge mistake and can result in expensive repairs. When combined, they can form a thick, jelly-like substance that will clog your vehicle’s cooling system. This entirely stops all coolant flow, which can cause overheating. Other problems that may occur include a water pump and radiator damage. The water pump may overheat and stop working, and the repair cost can easily make you pass out on the floor.

As you’ve seen, mixing antifreeze is not a good idea. If it happens, make sure to have the entire system flushed out before hitting the road. This is how you can be sure your cooling system is clean and not at risk. Failure to do so often leads to engine failure and costly repairs.

Common Types Of Antifreeze

While there are numerous types of antifreeze, the main two types of antifreeze used for a car are the orange antifreeze that uses Dexcool and the traditional green antifreeze. However, while the color can be a great starting point to determine what kind of coolant you have, it can sometimes be misleading.

For example, not all vehicles with orange antifreeze have Dexcool. When you mix Dexcool to your ordinary orange anti-freeze, you’re looking for trouble. Make sure to double-check the type of coolant in your vehicle – don’t solely count on color.

Green Antifreeze

The green coolant used to be the only type of coolant available and is by far the most common type of coolant in cars. This means that if you have an older car, it probably still uses green antifreeze. If you have a green coolant, you have an Inorganic Acid Technology (IAT) coolant. This type of coolant is sometimes known as a conventional low-silicate coolant because it uses silicate as a corrosion inhibitor.

Even though green coolant (or green antifreeze) doesn’t necessarily last long, ensure you double-check your car’s recommended service interval before rushing to flush out the antifreeze every few miles.

This is because most modern cars are getting much better, and with a sealed cooling system which lets the fluid last longer between changes. It’s therefore vital you peep into the owner’s guide before flushing your system.

Note that these intervals are for the owners-recommended coolant. Therefore, if you’re using something else, the service intervals will likely change as well. Green antifreeze is good for about 36,000 miles or three years, according to the manufacturer.

Orange Antifreeze

An orange antifreeze is an example of an Organic Acid Technology (OAT) coolant. Orange coolant uses organic acid as the inhibitor. It’s the type of coolant preferred for VW, Saab, and GM vehicles.

Although green antifreeze is the most popular coolant, orange antifreeze is also fairly prevalent. The difference between orange and green antifreeze is the product’s life. Orange coolant, often named Dexcool, still contains ethylene glycol and has other additional additives to increase its lifespan.

GM manufactured Dexcool and promised its users that they’d only have to flush their system every 150,000 miles if they used it. However, the coolant didn’t always work as advertised. Most drivers had problems with it in the past. There were even lawsuits filed regarding the effects of Dexcool on cars.

The fact that you open your hood and see an orange coolant doesn’t mean you have Dexcool. Double-check the type of coolant that’s in your vehicle instead of just relying on color. There are other kinds of orange antifreeze out there that are not Dexcool. For instance, Original Equipment Manufacturer (OEM) has orange antifreeze in their lineup, which is formed to work solely in Jeep, Dodge, and Chrysler vehicles.

If you’ve never flushed out the antifreeze in your vehicle, check the manufacturer’s guide. If you happened to change your car’s coolant, you might be unfortunate. But when you’re not sure, flush off your entire system before mixing the wrong coolant. Remember, there’s no good outcome to testing out can you mix antifreeze.

Less Common Types Of Antifreeze

While the green and orange antifreeze are essentially the most common types of antifreeze, there are other varieties too. In the last 20 or 30 years, several companies began producing other forms of coolants in different colors. The colors are meant to match different car makes and manufacturers. However, it can be somewhat confusing for the typical consumer to try to differentiate them.

The difference between this antifreeze varies, but it’s usually as a result of the additives used in each coolant. They’re all alcohol-based, but the type of additive used in each coolant is what makes a significant difference.

If you cannot determine the exact coolant your car uses, stop by your local dealership or flush out the whole system before replacing it with a new coolant.

Blue Antifreeze

There is actually a variety of blue antifreeze out there that you can get immediately. Some are a lighter shade of blue, while others are a darker shade of blue. Either of these types is formulated to be used in Japanese cars like Infiniti, Nissan, Mazda, and Mitsubishi. It’s supposed to be free of corrosion additives and an extended life coolant that can serve you for almost five years.

Can you mix antifreeze

Similarly, the other formulation of blue antifreeze performs the same task, but it’s only meant for Subaru, Honda, and Acura vehicles. The only difference between the two is that they contain some slightly twisted amounts of additives for anti-corrosion.

Generally, standard green antifreeze can also perform well in either of these vehicles. But just like some cars are designed to work with premium gasoline though you can use the regular one; if you are looking for an ideal coolant, you could use one of these formulations for your Mitsubishi, for example, instead of the standard type.

Yellow Antifreeze

The yellow coolant is an extended life coolant like the blue antifreeze but only works best with Hyundai and Kia vehicles. This type of antifreeze can serve you for about five years.

Gold Antifreeze

The gold antifreeze is some sort of a rich yellow-orange liquid that could easily be mistaken for oil at a glimpse and comes in various formulations. One formula is meant to work in Ford’s vehicles, such as Mercury and Lincoln. The other type is a European blend that’s meant to work in vehicles such as BMW, Volvo, Jaguar, Mercedes-Benz, and the mini.

Pink Antifreeze

Pink antifreeze comes in two different formulations. One meant for the Japanese vehicles and the other for the European cars. The European formulation marketed by OEM is essentially a pink liquid but stored in a purple bottle. It’s, however, supposed to work with Audi, Volkswagen, and Porsche vehicles.

The Japanese formulation is meant to work with Toyota and related manufacturers like Lexus and Scion and should keep your vehicle running for about five years. Again, the common green antifreeze we’re used to would work well in all these vehicles. You don’t have to stick to the special formulations in any specific vehicle.

Choosing The Right Antifreeze For Your Vehicle

An engine’s antifreeze is just as important as oil when it comes to your vehicle. As we mentioned earlier, it helps prevent the engine from freezing or overheating in extreme climates. And when it comes to adding or replacing, you’re going to have to find the proper antifreeze for the job. That’s instead of trying to experiment on whether can you mix antifreeze.

The right antifreeze for your car depends on the type of your vehicle, age, and place of manufacture. Knowing your car’s make, model, and year of manufacture will help you choose a suitable coolant for your vehicle. Selecting the wrong coolant will result in poor performance or even engine failure. The following steps will help you make the right choice.

Check The Color

Different coolant colors correlate with different car compatibility. For instance, IAT coolant is typically green, while HOAT is turquoise. However, remember that color isn’t necessarily a complete indicator of the ideal antifreeze for your car.

There are several brands designed for certain types of vehicles and countries of origin, which can bring about confusion due to the variety of colors. Always read what the bottle says before filling up and not rely on the specific color you’re pouring.

Head-On To The Source

If the bottle’s guidelines got you tripped up, check the owner’s manual to validate the antifreeze compatibility with your vehicle. Your owner’s manual contains vast sums of information. It will guide you on the best antifreeze for your car.

If you don’t have access to your owner’s manual, you can as well find the information you need online. The formula suggested in your owner’s manual and your dealership will probably be OEM approved. But there are likely other market varieties to choose from.

What About The Water?

If you’re changing your vehicle’s antifreeze, make sure to read the bottle to see if the formula ought to be mixed with water. And if yes, to what proportion. Some coolants can be poured into a car’s system without additives, but others are meant to be mixed 50/50 with water. Soft tap water does the trick.

Your vehicle’s performance matters a lot; therefore, be accurate when measuring out the ratio. Creating an antifreeze that’s too strong or too weak can lead to poor performance. Your car model can dictate whether a pre-diluted antifreeze or the one you can dilute yourself is the best.

Adding Or Replacing Antifreeze

For starters, the owner’s manual provides detailed guidance on how to add or replace your car antifreeze. Coolants/antifreeze are usually sold as a complete solution that should be diluted with water to form a 50-50 blend. The best part is you can do this all by yourself or get yourself a pre-diluted solution.

If your area’s temperature often drops to -34⁰F, then a 60-40 or 70-30 antifreeze ratio to water is essential.

As far as the antifreeze color is concerned, coloration does not affect its efficiency. Manufacturers achieve antifreeze color by use of various dyes, and orange and pink colors are a result of organic acids, while green antifreeze points to the use of silicates and phosphates.

Regardless of a certain antifreeze quality, a car coolant should be changed once every two to five years (average time after which it begins to lose much of its benefits). Failure to change your engine coolant could result in significant damage if your engine begins to overheat.

Overheated Engine Problems

If your vehicle continues to run without the proper antifreeze, either because you’ve mixed it or don’t have it off, you are risking an overheated engine. And you don’t want your engine to run hot. While it doesn’t seem a big deal to most people, it could lead to serious engine problems and the most expensive repairs a car has to face.

1) Damaged Hoses

The hose transports the antifreeze to the radiator, where it’s cooled, then back to the engine to keep your vehicle from overheating. When your car overheats, the antifreeze itself boils and expands just like any other liquid. This could result in a build-up pressure within the hoses that expands and detaches them from the engine or radiator.

2) Warped Cylinder Heads

A warped cylinder head is also a critical issue for vehicles. This means your car cylinder head is misshapen enough that it could cause leaks underneath your hood because it doesn’t seal or sit in a place like it was designed to.

When your car overheats and continues to run hot, the cylinder head gets warped. And if left untreated, this could cause several engine misfires, which could potentially lead to a broken head gasket.

3) Broken Head Gasket

A gasket failure could be caused by engine overheating more often (due to a coolant leak, clogged radiator, faulty fan, etc.), but blowing your engine’s head gasket will cause your engine to overheat as well. Hot gases can leak into the antifreeze, or antifreeze can leak into the cylinders and be burned off as steam. And in doing so, you’ve just killed your engine.

Smoke will start coming out of the vehicle, and the fix will likely be to rebuild the entire engine. Unfortunately, this repair is expensive, and if the car is driven while overheating, the steam can damage the catalytic convertor, adding significantly to the repair cost.

How To Prevent Engine Overheating

The best way to prevent these engine problems is to prevent what causes them. For instance, have you been silly and mixed coolants together before whether can you mix antifreeze? Fortunately, overheating is not a difficult thing to prevent, and doing so will help you save a lot of money in the long run. Remembering a few tips as you drive can help to alleviate permanent engine damage down the road.

1) Inspect Your Engine Belts

Different types of engines and cars have different belt systems. Some have multiple, smaller accessory belts, while others have one long winding belt. The belts transmit energy from the engine to its vital components, such as the water pump and fan. Therefore, if your fan belt falls off or breaks, your vehicle’s cooling system will fail, and the engine will probably overheat immediately.

Here’s a video on how to inspect your fan belt

2) Inspect Your Radiator Cap Often

The radiator cap plays a massive responsibility in your vehicle’s cooling system. It maintains your system to prevent overheating. The cap is spring-loaded, and with time, it becomes weak and worn out, resulting in minor air leaks. This subsequently leads to decreased pressure in the system, which may easily result in an overheated engine.

Don’t touch your radiator cap when your engine is hot! It’s under pressure, and the liquid inside is extremely hot. Make sure the engine is cool prior to performing any maintenance.

3) Make Sure Your Radiator Is Filled-Up With Coolant

Your car’s radiator depends on coolant to function appropriately and keep the engine temperature under control. Therefore, you must frequently check it and ensure it’s filled up before driving.

4) Clean Your Condenser

Debris and dirt tend to amass and pile up at the front of your car. With air-conditioning, your condenser will take the effect of this backlog. Since the condenser is positioned in front of the radiator, congestion at this point prevents airflow to the radiator, impeding engine cooling.

Cleaning your condenser helps decrease pressure, thus increasing the efficiency of your car’s cooling system. Air-conditioners are basically heat exchange systems. They take heat off the engine and transfer it outside via the condenser.

Facts about Mixing Antifreeze Brands and Colors:

  • Mixing different brands and colors of antifreeze can be tricky, and the wrong mix can lead to gelling, corrosion, or frozen cooling systems.
  • Not all colored coolants are the same, and while they may contain the same chemicals, different technologies can affect their performance.
  • Colored coolants have specific applications and additives that give them their unique color, indicating their use and whether they are suitable for a particular type of engine.
  • While some companies specify that certain coolant colors cannot be mixed, others may provide information on compatible colors that can be mixed, and it is essential to check with the manufacturer before mixing antifreeze.
  • It is generally safe to mix same-color coolants, but it is still better to use only one coolant color at a time to ensure they have the same freezing point.
  • Mixing different types of antifreeze, such as red and orange antifreeze, can cause freezing-point depression, leading to adverse effects on engine performance.
  • To avoid engine corrosion or damage, you must ensure that you use the same brand and type of coolant when mixing blue and green coolant.
  • Mixing green and yellow antifreeze can result in a blue-colored solution that can damage the cooling system or engine due to differences in their chemical composition.
  • You should not mix pink and blue antifreeze as they have different molecular weights and densities, and mixing them can result in a useless and unattractive mixture called “pink slime.”
  • You can mix pink and orange antifreeze, but it is best to let an expert mix them to avoid damaging the engine. You should avoid mixing coolant with tap or distilled water, as it can cause mineral deposits that may lead to costly repairs.

Can You Mix Antifreeze? – Bottom line

As we’ve seen, mixing antifreeze is not a good idea as it could lead to severe and costly repairs. But if it happens, flush off the entire fluid in your system before switching up the antifreeze. It’s the best and safest way to keep your car in good condition and ensure you’re not going to damage any part of your vehicle.

Also, follow the above maintenance tips to avoid overheating and eventually significant repair costs.

However, none of this helps when you forget the process a few months down the line. So, keep notes on the type of antifreeze you used and when to be prepared if your engine needs flushing. And remember, the consequences to ‘can you mix antifreeze’ will forever be a terrible mistake.

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1 comment

A. Junkie October 6, 2022 - 3:50 am

This is the worst article I have ever seen on the topic. Mixing antifreeze is not the cause of gelling, air intrusion into the system does…. a LEAK.

Ethylene glycol anti freeze all mix just fine, even old IAT green. Many products are the exact same anyway, these guys just don’t know the difference. Try mixing one Universal coolant with another Universal coolant and get back to me.


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