Posted under Car Fluids


Let’s take a pop quiz (sorry) – 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. 

Now that winter is here it means it’s time to prep 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!


Radiator fluid is basically 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, warming the engine block 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 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. 


It’s important to choose the correct radiator fluid for your vehicle 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 a 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. 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 very overheating or freezing that radiator fluid is designed to avoid.  So, if you’re unsure, do a double check to avoid mixing.


On most vehicles, you can check your coolant level by peeking into the radiator fluid reservoir tank. Wait until your engine is cool, then simply pop the hood of your vehicle, identify the coolant reservoir (usually a small transparent tank with MAX {maximum}/MIN {minimum} or FULL/ADD lines marked on the side), and look for a cap with “engine coolant” or “antifreeze” stamped on the top. The radiator fluid should be visible with the fluid level between the two points marked on the tank. If the radiator fluid is discolored, that’s a sign the additives are worn out and that it may be time to flush and refill your vehicle’s cooling system. If the radiator fluid looks cloudy or milky, this may be a sign of possible contamination with a petroleum product such as engine oil or transmission fluid. If this is the case, you should have your vehicle inspected immediately by a qualified technician. 



Radiator fluid should be topped off whenever the level in the reservoir drops below your tank’s MIN or ADD guidelines. Make sure that you have the correct radiator fluid and mix or dilute it as specified in the vehicle owner’s manual. After your radiator fluid is prepared, remove the cap from the reservoir tank and pour the mixture in until you reach the MAX/FULL line. Install the cap, turning until it clicks into place securely. If your vehicle does not have an overflow reservoir tank, you’ll need to add the radiator fluid directly to the radiator. Remove the radiator cap and pour the radiator fluid in a little bit at a time. You may need a funnel to help prevent spills on the engine or the ground. Continue to pour until you reach the bottom of the radiator filler neck and then re-secure the radiator cap. 

If it’s time to replace the radiator fluid entirely, you’ll need to flush your entire cooling system, removing all old radiator fluid before refilling your cooling system.


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 highly 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 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 the life of the vehicle.  Whether it’s hot, cold, warm or cool – bring it on to Jiffy Lube.