How to Choose the Right Coolant for Your Heavy-Duty Truck

If your heavy-duty truck sputters to a halt with white smoke rushing out your hood, the culprit is likely a coolant leak. Coolant leaks lead to overheating, causing your vehicle to come to a stop. A faulty cooling system can cripple your operations and cost you time and money. The good news is that you can prevent overheating by choosing the right coolant. Coolant plays a vital role in regulating your engine temperature, protecting it from both freezing and overheating. Choosing the wrong coolant can lead to engine damage, breakdowns, and costly coolant system repairs.

Understanding Coolant Types

Coolant does more than just prevent your engine from freezing in harsh winter conditions. It also protects your engine from corrosion, cavitation (the formation and collapse of bubbles in the coolant), and excessive temperatures. There are three main types of coolants used in heavy-duty trucks:

• Inorganic Acid Technology (IAT): Traditional green coolants, IAT coolants are formulated with inorganic salts like silicates and phosphates. These provide good corrosion protection for older engines but have a shorter lifespan and require more frequent replacement, typically every 2-3 years or 30,000 miles.
  
  
• Organic Acid Technology (OAT): Extended-life coolants, OAT coolants are typically orange or yellow and use organic acids for corrosion protection. They offer longer service intervals (up to 3-5 years or 150,000 miles) compared to IAT coolants and are compatible with aluminum components found in modern engines. OAT coolants are a popular choice for heavy-duty trucks due to their extended performance and reduced maintenance requirements.
  
  
• Nitrite-Free Organic Acid Technology (NOAT): The latest generation of coolants, NOAT coolants are similar to OAT coolants but eliminate the use of nitrites. Nitrites, while effective at corrosion protection, can degrade certain engine components like head gaskets over time. NOAT coolants offer excellent performance and extended service life for modern heavy-duty truck engines, making them the environmentally friendly choice without sacrificing protection.

Choosing the Right Coolant

The key to choosing the right coolant is ensuring compatibility with your specific truck's engine and cooling system. Using an incompatible coolant can lead to a variety of problems, including:

• Corrosion: Incompatible coolants may not provide adequate corrosion protection, leading to premature wear on engine components like the radiator, water pump, and heater core. This can result in costly repairs down the road.
• Gelling: Mixing different coolant types can cause them to gel, clogging the cooling system and restricting coolant flow. Reduced coolant flow can lead to engine overheating and potential damage.

Here are some key factors to consider when choosing a coolant:

• Manufacturer recommendations: Always refer to your truck's owner's manual for the recommended coolant type and specifications. The manufacturer will specify the appropriate coolant technology (IAT, OAT, or NOAT) and coolant mixture ratio (coolant concentrate and water).
• Engine type: Modern engines with aluminum components may require specific coolant formulations like OAT or NOAT for optimal protection. Aluminum is more susceptible to corrosion than traditional cast iron engine blocks, and these coolants are designed to provide better compatibility.
• Climate: If you operate your truck in extreme temperatures, consider a coolant with a higher freeze protection and boiling point. For example, if you experience harsh winter conditions, you'll need a coolant with a lower freezing point to prevent the coolant from freezing and potentially cracking the engine block.

Maintaining Your Cooling System: Prevention is Key

Choosing the right coolant is just one piece of the puzzle. Regular maintenance of your truck's cooling system is essential to prevent overheating and costly coolant system repairs. Here are some key maintenance practices to integrate into your routine:

Coolant level checks

Regularly check your coolant level, typically every other week or before long trips. Consult your truck's owner's manual for the proper location of the coolant reservoir and the recommended fill level. A low coolant level can indicate a leak or overheating issue. Adding the proper coolant mixture (consult your owner's manual for the recommended ratio of coolant concentrate and water) will help maintain optimal coolant system performance.

Coolant flushes

Over time, coolant can degrade and lose its effectiveness. Coolant can become contaminated with debris, rust, and other particles, reducing its ability to transfer heat efficiently. Schedule periodic coolant flushes, typically every 2-5 years or 300,00 to 150,000 miles depending on your coolant type and manufacturer recommendations. A coolant flush involves draining the old coolant, flushing the system with clean water, and refilling it with fresh coolant.

Thermostat checks

The thermostat is a vital component in the engine cooling system. It regulates coolant flow by opening and closing based on engine temperature. Symptoms of a faulty thermostat can include engine overheating, running cold, or inconsistent temperature gauge readings. If you suspect a thermostat issue, have it inspected and replaced by a qualified technician.

Cooling system inspections

Visually inspect your cooling system for leaks, cracks, or loose hoses at least once a month. Pay close attention to areas around the radiator, water pump, heater core, and hose connections. Look for signs of coolant leaks, such as puddles beneath the truck, coolant drips, or a low coolant level that requires frequent topping off. Early detection and repair of coolant leaks can prevent further damage and costly repairs.

Coolant additives

While not always necessary with modern coolants, some heavy-duty truck operators choose to use coolant additives. These additives can offer additional benefits such as improved corrosion protection, increased lubricity for the water pump, and enhanced heat transfer. However, it's important to consult your owner's manual and choose additives compatible with your specific coolant type. Using incompatible additives can have negative consequences for your cooling system.

Conclusion 

By understanding the different types of coolants, choosing the right one for your truck, and implementing a regular maintenance routine, you can significantly reduce the risk of engine overheating and costly coolant system repairs. A properly functioning cooling system is essential for optimal engine performance, fuel efficiency, and overall truck longevity. 

At Mobile Transportation Group, our certified technicians are experts in heavy-duty truck cooling systems. We can help you choose the right coolant for your specific vehicle, perform comprehensive cooling system inspections and maintenance services, and diagnose and repair any coolant leaks or malfunctions. Don't wait for a roadside breakdown to address cooling system concerns. Schedule a preventative maintenance inspection at Mobile Transportation Group today! Read our other articles to learn more about heavy-duty trucks. Find out how to choose the right tires for your fleet.