Diesel Engine Coolant

Cummins Racing & Pulling Engine
January 10, 2024

Diesel coolant is essential for proper vehicle operation. Coolant circulates within an engine to absorb and dissipate heat, and a diesel engine requires the right type of coolant to prevent engine overheating, freezing and potential failure. Engine coolant for diesel trucks and construction equipment contains additives to protect engine components from corrosion, cylinder cavitation and pitting. Diesel antifreeze further safeguards the engine by preventing freezing.


What Is Diesel Coolant?

Diesel engine coolant is a liquid that helps regulate an engine’s temperature. It works by circulating throughout an engine, absorbing and dissipating the heat the engine produces as it operates. The heat absorption and dissipation prevent the engine from overheating in the summer and freezing in the winter so the vehicle can run safely and effectively.

Coolant for diesel engines is slightly different from the coolant gasoline-powered vehicles use because it contains special additives to protect vehicles.


Importance of Diesel Engine Coolant

Diesel engines require more attention than other vehicles, and coolant is especially important if you drive a vehicle with a diesel engine. Using the proper coolant is crucial for safe and reliable vehicle operation, and ensuring your diesel vehicle maintains the correct coolant levels offers several benefits:

Proper Operation

Diesel engines are more prone to overheating than gasoline-fueled vehicles. Coolant is crucial to preventing an engine from overheating or freezing, and it helps prevent your car from breaking down. Using the right coolant and maintaining proper levels keeps your vehicle operational and on the road with fewer interruptions.

Engine Component Protection

Since coolant dissipates the heat an engine produces, it protects critical components from damage. Diesel engine coolant also carries additives such as anti-foaming agents and corrosion inhibitors to protect your vehicle from cylinder pitting and cavitation. 

Cavitation Prevention

Smaller, dry-sleeve engines and larger, wet-sleeve engines require coolant, but specific diesel engine coolant is especially essential for wet-sleeve engines. A wet-cylinder engine’s sleeve contains the engine’s piston, and the sleeve has direct contact with the coolant in its system, allowing it to dissipate more heat. Since the coolant comes in direct contact with a wet-cylinder engine’s iron sleeve, it is more susceptible to cylinder wall cavitation, and the engine has specific coolant requirements. 

Cavitation describes when small bubbles form behind an engine’s cylinder walls due to the walls vibrating against the engine’s piston, and diesel coolant is a heavy-duty solution containing additives to prevent cavitation.


Choose the Right Coolant

Diesel engines require adequate lubrication to operate smoothly, so choosing the correct coolant is crucial. The best type of coolant for a diesel engine is one with a high glycerol level because it provides the most effective lubrication. Most coolants contain 30% to 70% glycerol, but the best coolants are up to 95% glycerol.

Understanding the different types of coolants can help you choose the best option for your vehicle.


Inorganic acid technology (IAT) coolant is popular for its cost-effectiveness. Its quality is lower than other options, but owners of older cars tend to use it due to its lower cost.


Organic acid technology (OAT) coolant is a newer, more refined type of antifreeze than IAT. It’s made with ethylene glycol, and it requires few replacements. With OAT coolant, you can drive up to 150,000 miles or five years before replacing your antifreeze. OAT is a popular option in Europe because its composition provides the best protection for European cars.


Hybrid organic acid technology (HOAT) combines OAT and IAT coolants for a cost-effective but high-performance option for drivers. HOAT is the newest coolant solution, allowing you to drive your vehicle for 150,000 miles or three years before replacing the antifreeze. Automotive professionals trust this new solution for diesel vehicle maintenance.


How to Properly Replace Your Coolant

While most high-quality coolants can last up to 150,000 miles or three to five years, replacing them more frequently is best for your vehicle’s operation and life span. Your control board can indicate when it’s time to replace your antifreeze, but you should also inspect your engine periodically to check coolant levels. 

The best time to check coolant levels is when the weather starts to shift. We recommend inspecting your coolant reservoir tank during the end of summer or the beginning of fall before the colder weather begins to approach, and you should recheck it toward the end of winter and the beginning of spring before summer temperatures begin to rise.

You can locate your coolant reservoir tank by reviewing your vehicle manufacturer’s manual. Once you find the diesel antifreeze reservoir, look at the coolant’s level within the tank. If it seems low, you should replace it to ensure you have an adequate amount for the upcoming season. You can also seek assistance from a professional mechanic to ensure you maintain it properly. 


Why Should You Choose Hot Shot’s Secret?

Hot Shot’s Secret is dedicated to improving our customers’ lives by helping them maintain their engines. Our high-quality solutions can help you address engine challenges easily and have peace of mind that your vehicle is in top shape.

Our team consists of experienced professionals with the skills and knowledge to address diesel and gasoline-powered engine needs. We provide highly concentrated formulas to outperform the diluted products you commonly find in retail stores, and we are passionate about helping you solve engine challenges other products cannot repair. 


Maintain Your Diesel Engine With High-Quality Coolant From Hot Shot’s Secret

Hot Shot’s Secret offers diesel coolant that exceeds industry standards. Our 750,000-mile Heavy-Duty Ultra-Long Life Red antifreeze is a 50/50 mix with distilled water and contains supplemental additives. This antifreeze is compatible with other extended-life and conventional brands.

Hot Shot’s Secret’s diesel coolant is specifically made for heavy-duty vehicles and can last up to 750,000 miles. Whether you drive a diesel truck or operate construction equipment, our diesel coolant can help you protect your engine’s components and prevent engine failure. Purchase Hot Shot’s Secret’s top-quality antifreeze online or locate a store near you to enhance your engine’s performance, safety and life span.