Let’s take a pop quiz – true or false: Antifreeze and coolant are the same thing. The answer…TRUE! To make things easier, these products are collectively known as radiator fluid. So, when in doubt, just use that term.

When the temperature drops, it’s a good time to prepare your vehicle for freezing temperatures, salty roads, and slushy driving conditions. Many people know that when it’s freezing outside, their radiator needs antifreeze or engine coolant. And now you know that antifreeze and coolant are basically the same thing and can be generically referred to as radiator fluid. And you also know this fluid is key to keeping your vehicle engine in good working order and helps prevent it from freezing or overheating in any weather. So, bring it on, Mother Nature!

What Is Radiator Fluid, Anyway?

Radiator fluid is the unsung hero of your car’s cooling system, helping your engine maintain the correct temperature no matter what the weather. It’s a mixture of chemicals and water that goes by different names depending on the situation—“coolant” when referring to it during warmer weather, and “antifreeze” when referring to it during colder weather.

This fluid does double duty to protect your car. In freezing temperatures, it prevents the liquid in your cooling system from turning into ice by lowering the freezing point. In sweltering heat, it keeps your engine from overheating by raising the boiling point of the fluid. In a nutshell, radiator fluid ensures your engine stays cool, calm, and collected in every season.

How Antifreeze and Engine Coolant Work

Radiator fluid is a mixture of chemicals that enhance anti-freezing as well as anti-overheating properties and include corrosion inhibitors. It acts as a means of heat transfer for the engine, helping the engine block warm up evenly when it’s cold and drawing heat away from components when it’s hot. The cooling system runs in a loop, flowing through the engine and heater core before reaching the radiator and starting all over again. Vehicle manufacturers take all types of weather and engine construction into consideration when specifying their radiator fluid, so it’s designed to protect your vehicle in both hot and cold weather extremes. The corrosion inhibitors also protect the engine and its cooling system from the build-up of any scale, rust, or contaminants that can degrade their operation over time. Without radiator fluid, your engine may overheat or seize up, causing extensive damage to your vehicle and possibly leaving you stranded.

Types of Radiator Fluid

Choosing the correct radiator fluid for your vehicle is important because there are many types, each distinguished by their formulations, such as the kind of corrosion inhibitor used in their mixture. Corrosion inhibitors can be organic, inorganic, or hybrid. Many of these formulations work by coating the inside of engine components in a layer of protective film that reduces friction, cleans the components, and stops deposits from building up. Let’s look at the main types of radiator fluid:

• Inorganic Additive Technology (IAT): This traditional green coolant is designed for older vehicles. It uses inorganic corrosion inhibitors to protect your engine but needs to be replaced more frequently than other types (roughly every two years or 24,000 miles).
• Organic Acid Technology (OAT): OAT coolant is often orange or red and is a long-life option commonly used in newer vehicles. It relies on organic acids to protect against corrosion and can last much longer between changes (about 50,000 miles or five years).
• Hybrid Organic Acid Technology (HOAT): A blend of IAT and OAT, HOAT coolant offers the best of both worlds. It’s often yellow or blue and is compatible with certain modern vehicles, providing robust corrosion protection and extended life (approximately every five to ten years).

There are multiple types of radiator fluid on the market, but the most important thing to know is that they should never be mixed, and it’s best not to switch types between refills. Mixing radiator fluids can create a gel byproduct that may clog the cooling system passages within your engine, resulting in the overheating or freezing that radiator fluid is designed to avoid. So, if you’re unsure, do a double check to avoid mixing.

Signs It’s Time to Check or Replace Your Radiator Fluid

Your radiator fluid is key to keeping your engine healthy and knowing when to check or replace it can save you from costly repairs. Here are a few signs that it might be time for some attention:

• You’ve reached your vehicle manufacturer’s recommended time/mileage: Check your vehicle owner’s manual to determine the time/mileage that applies based on your driving style/conditions.
• Your engine temperature warning light comes on: If this light pops up on your dashboard, it’s a clear signal that something’s up. Your coolant level might be too low, or it’s not doing its job.
• You smell something sweet under the hood: That sugary smell? It’s often a clue that there’s a coolant leak. Don’t ignore it — leaks can lead to bigger problems quickly.
• Your radiator fluid looks weird: Radiator fluid should be bright and clean (usually green, but sometimes red, yellow, or pink). If it’s discolored, cloudy, or even rusty, it’s time for a flush.
• Your engine is overheating out of nowhere: If your engine is running hot without a clear reason, your radiator fluid might be the culprit. It could be low, dirty, or unable to flow properly.

Visit Jiffy Lube for Radiator Fluid Maintenance

Remember our pop quiz at the beginning — this isn’t about antifreeze vs. engine coolant, as they are the same and can be referred to as radiator fluid. Radiator fluid should be replaced regularly based on the type used, the number of miles driven, and the age of the fluid. You can check your vehicle manufacturer’s recommendations by looking at the owner’s manual. It’s a best practice to visually inspect your radiator fluid level when the season changes (especially in anticipation of the more extreme summer and winter temperature changes) and to flush and replace your coolant based on manufacturer recommendations.

Fortunately, whether you’re looking for a routine cooling system check or need to flush the entire system, you can stop by Jiffy Lube^®, where trained technicians have access to the radiator fluid specifications for every vehicle make and model and can help ensure your vehicle gets the correct type and amount of radiator fluid to perform at its best. Impressive, right? And as part of the service, Jiffy Lube will test your vehicle’s cooling system, assess your needs, replace it with the necessary radiator fluid, and properly dispose of your old radiator fluid. Keeping your vehicle’s cooling system properly filled will help get the best performance from your vehicle and help extend its life, so visit your local Jiffy Lube to top off your radiator fluid.