What Are The Different Types Of Coolants Used In Semi Trucks?

Car,coolant,system,close,upCoolant and antifreeze are essential components for maintaining the proper temperature and preventing the system from overheating or freezing in semi trucks. Additionally, they play a crucial role in protecting the system against corrosion. In this blog post, we will explore the different types of coolants commonly used in semi trucks.

1. Ethylene Glycol Coolants

Ethylene Glycol coolants are one of the most widely used types of coolants in the automotive industry, including semi trucks. This type of coolant offers excellent heat transfer properties, making it highly effective in controlling the temperature within the engine. Furthermore, ethylene glycol coolants have a high boiling point, which helps to prevent the engine from overheating during prolonged use or under heavy load conditions.

2. Propylene Glycol Coolants

Propylene Glycol coolants are another popular choice in the market for semi trucks. Similar to ethylene glycol coolants, propylene glycol coolants have excellent heat transfer properties. However, they differ in their toxicity level. Propylene glycol coolants are considered less toxic than ethylene glycol coolants, making them a safer option for applications where there is a risk of coolant leakage or spillage.

3. Organic Acid Technology (OAT) Coolants

Organic Acid Technology (OAT) coolants are a more advanced type of coolant used in modern semi trucks. OAT coolants are free from silicates, phosphates, and nitrates, making them environmentally friendly. They are also compatible with a wider range of metals and materials used in engine components. OAT coolants provide long-lasting protection against corrosion and cavitation with less maintenance required.

4. Hybrid Organic Acid Technology (HOAT) Coolants

Hybrid Organic Acid Technology (HOAT) coolants are a blend of organic and inorganic acid technologies. These coolants offer enhanced protection against corrosion and cavitation while providing longer service life compared to traditional coolants. HOAT coolants are commonly used in semi trucks and heavy-duty engines where extended coolant life is desired.

5. Nitrite Free Extended Life Coolants

Nitrite Free Extended Life coolants are designed to provide long-lasting engine protection without the use of nitrites. Nitrite is a common component in traditional coolants and acts as a corrosion inhibitor. However, it can be harmful when exposed to human skin or eyes. Nitrite Free Extended Life coolants offer the advantage of extended coolant life without the potential health risks associated with nitrite-containing coolants.

6. Phosphate Free Coolants

Phosphate Free coolants are specifically formulated to eliminate phosphates from the coolant composition. Phosphates are known to cause scale build-up and may lead to decreased cooling efficiency over time. Phosphate Free coolants offer improved heat transfer properties and reduced maintenance requirements. They are commonly used in modern semi trucks to prevent scale formation and maintain optimal engine performance.


Coolants play a vital role in controlling the temperature and preventing corrosion in semi trucks. The choice of the coolant type depends on specific requirements, environmental concerns, and health considerations. Ethylene Glycol, Propylene Glycol, Organic Acid Technology (OAT), and Hybrid Organic Acid Technology (HOAT) are popular options for different applications. Additionally, Nitrite Free Extended Life and Phosphate Free coolants offer enhanced performance while addressing specific concerns. Regular maintenance and periodic coolant replacement are crucial for ensuring optimal performance and longevity of the cooling system in semi trucks.

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