A Guide to Engine Coolant: Types, Maintenance, and Replacement

Engines create a lot of heat—so much, in fact, that they are constantly in danger of overheating. That is why vehicles require engine coolant or antifreeze. This important substance is vital to ensuring your engine remains cool and runs well.

But what is engine coolant? Many people do not fully understand antifreeze, the different types of the product, how to maintain it, and when to replace it. In the rest of this guide, we will answer all of the pressing questions.

If, when you are finished reading, you still have questions about engine coolant, contact your local mechanic, such as Ethan’s Honest Automotive in the Cache Valley and Southeastern Idaho. Our experts can walk you through everything you need to know about engine coolant.

For now, let’s start with some basics.

What is Engine Coolant?

Engine coolant is a liquid substance used in vehicles to regulate engine temperature. It circulates through the engine and absorbs heat generated when the engine is running, helping to prevent the engine from overheating. Coolant also has another important function: In colder temperatures, such as winters in the Cache Valley, it prevents the engine from freezing.

Engine coolant circulates through a closed system, which includes the radiator, water pump, hoses, and engine block. As the coolant absorbs heat from the engine, it flows to the radiator, where it releases heat into the surrounding air. The cooled coolant then returns to the engine to continue the cooling process.

Types of Engine Coolant

All engine coolant is made of a mixture of water and additives. The most common additives are ethylene glycol or propylene glycol. However, you may find other additives as well. The variation in additives defines the various types of coolant.

Talk with your mechanic about the best types of coolant for your vehicle. They will likely recommend one of the following.

• Ethylene glycol-based coolants: These are the most common types of coolant found in vehicles. Ethylene glycol-based coolants come in various formulations, offering different levels of protection against freezing and boiling. They typically contain additives to prevent corrosion, scale buildup, and foaming.
• Propylene glycol-based coolants: Unlike ethylene glycol, propylene glycol-based coolants are less toxic and safer for the environment. They provide similar protection as ethylene glycol-based coolants, and they often come premixed, making them convenient for most vehicle owners.
• Organic acid technology (OAT) coolants: OAT coolants are long-life coolants that use organic acids as corrosion inhibitors. They offer extended service intervals, typically ranging from five to seven years or 50,000 miles. OAT coolants are compatible with a wide range of metals and materials used in modern engine designs. They are also often required for vehicles made by large vehicle manufacturers, such as General Motors.
• Hybrid organic acid technology (HOAT) coolants: Finally, there are HOAT coolants. These products combine the benefits of traditional ethylene glycol-based coolants with OAT technology. They provide extended service life, as some vehicle manufacturers say they can be changed every 10 years or 150,000 miles. More common scheduled maintenance recommendations are every five years or 50,000 miles. HOAT coolants also offer compatibility with various metals and superior corrosion protection.

In addition to the coolant types listed above, there are specific types of coolant systems for hybrid and electric vehicles. If you own a hybrid or electric vehicle, contact Ethan’s Honest Automotive to learn more about your coolant system and its maintenance requirements.

How to Maintain Your Engine Coolant

To get the most out of your vehicle’s engine, you need to maintain your engine properly. That includes doing the following with your coolant.

• Inspect the coolant levels, hoses, and connections regularly: Check the coolant level and condition regularly, especially before long trips or extreme weather. When examining the antifreeze, look for signs of contamination, such as rust particles or oil. You should also periodically inspect coolant hoses and connections for signs of leaks, cracks, or deterioration.
• Flush and replace the coolant on time: Follow the manufacturer’s recommendations for flushing and replacing the coolant. Flushing the cooling system removes old coolant, debris, and contaminants. Depending on the type, the timeframe for both flushing and replacing the coolant will typically be every two to five years or 30,000 to 100,000 miles.
• Top-up coolant as needed: If you notice that the coolant level is low during your regular checks, top it up with a mixture of coolant and distilled water according to the manufacturer’s specifications. Do not use tap water, as it may contain minerals and impurities that can harm the engine.

Use the correct coolant: Ensure you use the coolant recommended by your vehicle manufacturer. You can find this information in your owner’s manual and by talking to a trusted mechanic at Ethan’s Honest Automotive

When to Replace Your Engine Coolant

As you learned in the last section, it is an important part of coolant maintenance to replace it on time. Yet, knowing when to replace the coolant can be a challenge for some vehicle owners.

Your owner’s manual provides information about when and how to replace the coolant. However, you should also look for the following signs.

• The coolant is cloudy, discolored, or contaminated with debris.
• The coolant levels are low or need to be regularly topped up.
• The engine consistently runs hotter than normal.
• You live in a climate with extreme temperatures and driving conditions.

If you notice any of the previous signs, it is time to consider replacing your coolant. You can also ask the team at Ethan’s Honest Automotive to test your coolant. This test helps them determine if a coolant replacement is necessary.

Engine coolant is a crucial component of every vehicle. Without it, your car will be prone to overheating and not run efficiently. By understanding the different types of coolant available, implementing proper maintenance practices, and ensuring timely coolant replacement, you can keep your vehicle running better for longer.

Always refer to your vehicle manufacturer’s recommendations and seek professional assistance from the experts at Ethan's Honest Automotive if you have more questions about coolant replacement and maintenance.