Can You Mix Prestone Antifreeze With Dexcool? [Compatibility]

Antifreeze is an essential fluid used in automobiles to prevent the engine’s coolant from freezing and overheating. Prestone Antifreeze and Dexcool are two of the most popular ethylene glycol-based antifreeze brands on the market.

But can you mix Prestone antifreeze with Dexcool? The answer is yes. Let’s explore why that is, what are the benefits of doing so and whether there are any risks associated with mixing different types of antifreeze.

Understanding Antifreeze Types

Choosing the right type of antifreeze is crucial for your car’s health. There are three types available: Inorganic Acid Technology (IAT), Organic Acid Technology (OAT), and Hybrid Organic Acid Technology (HOAT).

  • The bright green IAT is commonly used in older cars and needs to be replaced every 30,000 miles. 
  • OAT lasts longer and is usually orange, yellow, red, or purple. Although it can go for up to 150,000 miles, there’s no additional engine protection.
  • HOAT offers similar mileage and is typically orange or yellow.

Besides, antifreeze can be based on two main chemical types: ethylene glycol and propylene glycol. Ethylene glycol is more commonly used, while propylene glycol is often found in hybrids and electric vehicles as it’s less toxic.

The antifreeze you choose must be compatible with your car’s cooling system. It shouldn’t react with any metal or rubber parts and shouldn’t cause any damage or corrosion.

Read Also: Can You Mix Green and Yellow Antifreeze? (Don’t Do It)

What is Prestone Antifreeze?

Prestone antifreeze is an ethylene glycol-based OAT. This mixture of coolant and antifreeze is formulated to protect against rust, corrosion, boilovers, and overheating. It comes in yellow or green color and contains anti-corrosion chemistry, which helps it last up to 150,000 miles.

What is Dexcool?

Dexcool is another ethylene glycol-based antifreeze. According to MSDS, the presence is around 85%, similar to regular OATs. It’s typically orange or yellow. It provides superior protection against rust, corrosion, and overheating, and can last up to 150,000 miles.

Can You Mix Prestone Antifreeze and Dexcool?

Yes, you can mix Prestone antifreeze and Dexcool as both are ethylene glycol-based and provide similar levels of protection and longevity. While it’s generally not recommended to mix different types of antifreeze, in this case, there’s no harm in doing so. Here’s why:

  • Both Prestone and Dexcool are compatible with modern cooling systems.
  • Both share similar organic chemistry and won’t react with each other.
  • Both are OAT-based and provide similar levels of protection against rust, corrosion, and overheating.
  • Both have a life expectancy of up to 150,000 miles.

But you must keep in mind that Dex-Cool and Prestone exhibit different freezing points. As a result, the freezing point of the mixture will fall between Dexcool and Prestone. Meaning, if the mixture freezes, it will do so quicker than either type on its own.

Read Also: Can You Mix Yellow and Orange Antifreeze?

How to Mix Prestone Antifreeze and Dexcool?

When mixing Prestone antifreeze and Dexcool, you should always use equal parts of each. If using a 50/50 solution, use equal amounts of Prestone and Dexcool for a total of 1 gallon of antifreeze solution.

This is because the difference in freezing points between the two types of antifreeze needs to be accounted for. Using too much of one or the other can also lead to compatibility issues.

When pouring the mixture into your radiator, make sure it’s at the right temperature, so it blends well with the existing antifreeze and prevents the formation of scale. You can determine it by referring to your car’s owner’s manual or asking a professional.  

Also, make sure to close the system’s drain valve and purge air from the system by topping off the coolant with more Prestone or Dexcool to prevent air pockets from forming. 

Benefits of Mixing Prestone and Dexcool

Though some people avoid mixing antifreeze, combining Prestone and Dexcool has several advantages, such as:

  • Extending the life of your antifreeze: Mixing Prestone and Dexcool helps reduce the rate of oxidation so both types of antifreeze will last longer.
  • Enhancing the protection of your cooling system: The mixture of Prestone and Dexcool will offer the same level of protection as either antifreeze on its own.
  • Less sticky gunk: The combination of Prestone and Dexcool has been found to be creating less sticky and dissolving sludge and other fluids, which is easy to get rid of.
  • Cost-effective: Mixing Prestone and Dexcool is cheaper than buying and replacing multiple antifreeze types due to the solution’s extended lifespan.

Read Also: Can You Mix Orange And Green Antifreeze?

Why You Shouldn’t Mix Any Antifreeze?

While you can safely mix Dexcool with Prestone, you should remember that mixing any two types of antifreeze can create compatibility issues. 

Often, mixing different types of antifreeze can lead to a chain reaction of chemicals. It can lead to gel-like sludge buildup, which can obstruct and clog the small passages of the radiator, water pump, and other parts of the cooling system and reduce their efficiency.

For example, mixing a silicate-based antifreeze, like IAT, with an OAT or HOAT can lead to the release of silicates. These can react with other chemicals like phosphates to form sludge with high-concentration sediment, 

This can cause corrosion, overheating, clogging, leaks, and other damage to your car’s cooling system. In some cases, this could lead to engine failure. Also, always remember not to mix conventional IAT and OAT antifreeze, as they use different chemical technologies.

Read Also: Is It Safe Mixing Dexcool and Universal Antifreeze? (Explained)

Frequently Asked Questions

If you have further queries regarding mixing Prestone and Dexcool antifreeze, here are some answers to common questions that might help you out.

Is it safe to mix Dexcool with Prestone antifreeze?

Yes, you can safely mix Dexcool and Prestone antifreeze as they use similar ethylene glycol-based technology and provide similar levels of protection. As long as you’re using a 50/50 mix of the two, you’re unlikely to experience any compatibility issues.

What is the difference between Prestone antifreeze and Dexcool antifreeze?

The main difference between Prestone and Dexcool antifreeze is their freezing point. Prestone antifreeze has a freezing point of -35°F, while Dexcool antifreeze has a freezing point of -60°F. When mixed, the mixture’s freezing point will be somewhere in between.

What happens if I mix Prestone antifreeze with Dexcool antifreeze?

When you mix Prestone and Dexcool antifreeze, chemical reactions are unlikely. However, the mixture’s freezing point will fall between the freezing point of each antifreeze on its own. Yet, the mixture will offer the same protection against rust and corrosion.

Can I use Prestone antifreeze in a car that requires Dexcool antifreeze, or vice versa?

Yes, you can use Prestone or Dexcool antifreeze in a car that requires the other. However, you should always check the manufacturer’s recommendations before doing so as some vehicles may require a specific type of antifreeze.

Will mixing different types of antifreeze void my vehicle’s warranty?

It depends on your vehicle’s manufacturer and the type of antifreeze you’re using. Generally speaking, mixing Dexcool and Prestone antifreeze won’t void your car’s warranty. But you should always check with your car’s manufacturer or a qualified mechanic to confirm this.


Prestone and Dexcool are both ethylene glycol-based, so you can safely mix them together. This mixture offers the same level of protection against rust, corrosion, and overheating as either antifreeze on its own. 

Plus, it’s cost-effective, since it reduces antifreeze replacement multiple times due to its extended lifespan. However, you must not mix any type of antifreeze with different chemical technologies, which can damage your car’s cooling system.

Read Also: Can You Mix Red and Green Coolant? (Know Before Mixing)

Similar Posts