The Impact Of Proper Coolant Mixture And Additives On Truck's Engine Protection

December 5, 2023
Proper Coolant Mixture And Additives On Truck's Engine Protection

Did you know that Organic Acid Technology (OAT) coolants, a subset of heavy-duty truck coolants, typically provide an impressive 600,000 miles or 12,000 engine hours of service life? This longevity is a testament to the evolution of coolant and additive technology, offering fleet managers options that can significantly lower maintenance costs while extending the service intervals for crucial tasks like coolant top-ups, coolant flush and fill procedures, and overall engine protection.

In this article, we’ll be diving into the world of coolant/antifreeze technology, supplemental coolant additives, and the factors you should consider when choosing the right coolant mixture for your fleet.

Understanding the Basics of Coolants

Coolants play a pivotal role in safeguarding a truck's engine. Among the four primary types of truck coolants—Inorganic Acid Technology (IAT), Hybrid Organic Acid Technology (HOAT), Extended Life Coolant (ELC) or Nitrite Organic Acid Technology (NOAT), and Organic Acid Technology (OAT)—each comes with its unique characteristics and service intervals. 

IAT, often recognized as the mainstream green coolant, provides a standard service life, while HOAT extends it further due to its combination of some of the inhibitors found in inorganic and organic acid technologies.

ELCs and NOAT coolants are the newest of the bunch and are designed for prolonged use, offering an extended service life and minimal maintenance requirements.

In-Depth Analysis of Coolant Types

Inorganic Acid Technology (IAT)

Inorganic Acid Technology (IAT) coolants or conventional coolant mixtures, known for their mainstream green appearance, provide reliable service with standard maintenance intervals. Since the majority of IAT coolants available on the market come fully formulated with a pre-charge of Supplemental Coolant Additives (SCAs), designed to safeguard the cooling systems of heavy-duty engines from issues such as corrosion, cavitation, liner pitting, freezing, and boilover, fleet managers typically need to administer SCA at intervals of 25,000 miles or as specified by the engine manufacturer to ensure optimal performance.

Hybrid Organic Acid Technology (HOAT)

Hybrid Organic Acid Technology (HOAT) coolants strike a balance between traditional and extended-life coolants, offering a longer service life with additional additives. Given that HOAT coolants utilize a blend of inhibitors derived from both organic and inorganic acid technologies, similar to IAT coolants, they generally require the addition of SCAs back into the system. This should be carried out at the initial maintenance interval, set at 25,000 miles, or as outlined by the engine manufacturer.

Nitrite Organic Acid Technology (NOAT)

Extended Life Coolants (ELC) or Nitrite Organic Acid Technology (NOAT) go a step further, catering to heavy-duty applications with an extended service life and robust corrosion protection. They employ a combination of organic acids and nitrite, and unlike inorganic antifreeze variants, ELC coolants operate efficiently without the need for a supplement until 300,000 miles or 6,000 engine hours. 

This delayed supplementation ensures that ELC achieves its maximum service life of 600,000 miles or 12,000 engine hours.

Organic Acid Technology (OAT)

Organic Acid Technology (OAT) coolants, the frontrunners in the evolution of coolant technology, boast a remarkable service life of 600,000 miles or 12,000 engine hours without the need for additional supplementation. These coolants are characterized by their organic additives and lack of nitrite, which translates to minimal maintenance requirements and efficient engine protection.

Supplemental Coolant Additives (SCAs)

For conventional IAT and HOAT coolants, the consumption of additives during a vehicle's operation requires regular refortification with supplemental coolant additives (SCAs). These additives play a crucial role in maintaining effective corrosion protection. 

However, the advent of ELCs and OAT coolant technology has revolutionized this landscape. With their organic additives, these coolants eliminate the need for SCAs altogether, significantly reducing the maintenance burden for fleet managers. This feature not only simplifies the coolant service process but also ensures continuous and efficient engine protection without the need for frequent additive replenishments.

What Should I Pick for My Fleet?

While IAT and HOAT coolants are more budget-friendly, their cost-effectiveness must be weighed against the additional maintenance requirements. ELCs and NOAT coolants, with their extended service life, might demand a higher upfront investment, but they offer long-term benefits by reducing maintenance costs and enhancing engine protection.

Performance and engine protection are critical considerations when choosing a coolant for heavy-duty trucks. The choice must align with your fleet's specific operational needs, factoring in aspects such as coolant service intervals, maintenance requirements, and overall cost. The goal is to strike a balance between initial investment and long-term gains, ensuring that the chosen coolant type aligns seamlessly with the demands of your fleet.

Best Practices for Fleet Managers

Selecting the right truck coolant involves more than considering the type; it requires a comprehensive understanding of your fleet's composition and usage. Make sure you tailor your coolant choices based on the specific needs of your trucks, ensuring that the chosen coolant type aligns with the manufacturer’s specifications. 

Preventive maintenance is essential for monitoring coolant levels and coolant functionality. We suggest you develop a proactive schedule for coolant checks, coolant top-ups, coolant flush and fill procedures, and routine inspections to help catch any issues early on and ensure efficient engine protection. And, if you’ve opted for inorganic or hybrid acid technology coolants, don’t forget to schedule a coolant system service with your local diesel repair shop. 

Final Words

In the ever-evolving landscape of heavy-duty truck maintenance, the impact of proper semi-truck coolant selection cannot be overstated. The evolution of coolant and additive technology provides fleet managers with a spectrum of options, each with its unique benefits. From IAT and HOAT coolants to ELCs and OAT coolants, the key lies in making informed decisions that balance cost, performance, and environmental impact. As heavy-duty trucks continue to play a pivotal role in the global economy, the importance of proper coolant mixture and additives in ensuring engine protection and longevity remains a top priority for fleet managers navigating the complexities of modern truck fleet maintenance.