Antifreeze vs Coolant – Is Coolant the Same as Antifreeze?

July 19th, 2021 by

The terms antifreeze and coolant get used interchangeably by mechanics worldwide, which leads to confusion with car owners trying to understand the difference. At Sweeney Buick-GMC, we often get asked what is the difference between engine coolant and radiator coolant? No difference exists between these two names, as the fluid within both are the same. In fact, the radiator cools the engine coolant after it runs through the engine.

We also get asked, is coolant the same as antifreeze? The answer to this question is yes and no. Manufacturers of antifreeze create a solution called ethylene-glycol, which has anti-freezing properties. Coolant contains a mixture of antifreeze and distilled water, typically in a 50-50 blend.

engine coolant mixture ethylene-glycol and water

What Does My Car Use, Antifreeze or Coolant?

Most cars use coolant, that blend described above, to cool the engine. Most experts don’t recommend using 100% antifreeze in your vehicle’s cooling system. These experts believe the concentrated antifreeze can damage the system. Manufacturers recommend using a blend of antifreeze and water, usually in the 50-50 range, but some will suggest a 70-30 mixture. Be sure to consult your owner’s manual before adding any fluids to your car, especially your engine cooling system.

Why Do I Need Antifreeze or Coolant?

Your vehicle’s engine operates at high temperatures. The oil inside helps lubricate and protect the moving parts within your engine. The coolant runs through water jackets, hollow structures within the engine’s block, and absorbs the heat created by the combustion process. Next, the hot coolant goes to your car’s radiator, which cools it down by exposing it to air before returning it into the engine to repeat the process.

You need to change your engine oil regularly to maintain the appropriate lubrication that keeps the moving parts from seizing up. You also need to change your engine coolant regularly to achieve the proper cooling temperatures. Should the coolant weaken to the point of ineffectiveness, the engine’s temperature will heat to dangerous levels that deplete your oil’s viscosity (the ability to lubricate) and result in the seizing of your engine’s moving parts.

If your engine seizes, at the very least, you have an expensive re-build on your hands, or perhaps you’ll need an entirely new engine. Either way, a seized engine costs thousands of dollars to repair or replace. Your engine coolant costs $10-$20 per gallon, making it an inexpensive maintenance item that protects a costly part: your engine. Maintaining your engine coolant and radiator should be a high priority.

What are Antifreeze and Coolant?

green coolant pouring into engine

Antifreeze and coolant have a low freezing point and a high boiling point. Your engine coolant needs to have a high boiling point to prevent it from evaporating while traveling through your engine, where it gets exposed to extremely high heat. It also needs to have a low freezing point to protect against freezing in cold weather. If your coolant freezes, and you start your engine, the frozen coolant doesn’t travel through your engine block to cool it down, resulting in an overheated engine, or worse, a seized engine.

If you use the proper mixture of antifreeze and water, your engine should never overheat, unless you have other issues like a leak in one of your hoses. If you notice a leak, you should bring your car into Sweeney Buick-GMC for service right away. If your check engine light activates, or you receive an overheating alert, shut your engine off immediately to save it from damage.

You might need a tow, but in some cases, you can add water to your cooling system as a short-term solution to get you to our service center, or at least a safe place where you can wait for help. You can use water for extended periods during the summer or in areas that don’t experience freezing temperatures, but this practice has its drawbacks.

Water evaporates when exposed to the high heat of your engine, making it likely that you’ll overheat on any drive longer than a trip across town. You’ll also need to carry several gallons of water wherever you go to replenish the system. We don’t recommend drivers use only water in their cooling system.

How Often Should I Change My Engine Coolant?

Most mechanics recommend changing your engine coolant every 30,000 miles. Some manufacturers recommend changing your coolant at 60,000 miles and then every subsequent 30,000 miles. Check your owner’s manual for your specific vehicle’s requirements. Because of the long cycle between changes, tracking the need to change your engine’s coolant presents a challenge to most car owners. It isn’t as simple as checking your brakes every other oil change.

That’s why we recommend having your car, truck, or SUV regularly serviced with Sweeney Buick-GMC. Our service center technicians will keep track of your regular service and maintenance needs and notify you when you should change your engine’s coolant. You get peace of mind knowing your vehicle has received the proper care when you service with us.

How Do I Know When to Add Coolant?

Most cars have a reservoir located at the top of the engine compartment, usually toward the front. It should be clearly labeled and have a low line and a fill-to line marked on the side. You should check your coolant level at least once a month. When it gets to the low line, you simply pour in more coolant until the level reaches the fill-to line.

You should never attempt to open the reservoir or your radiator cap with a hot or running engine. The cooling system operates under pressure, and the hot liquid can spray out, scalding hands, face, and any other body part unlucky enough to be hit. If you need to add coolant between service appointments, we recommend waiting several hours for your car to cool down.

At Sweeney Buick-GMC, we know you don’t always have time or know-how to service your car yourself. That’s why our service center technicians receive factory training on everything Buick and GMC. Our technicians are experts at routine services and more involved maintenance and repairs. We use state-of-the-art diagnostic equipment and tools to identify and fix all your vehicle needs. Most regular services take less than 30 minutes to complete, including changing your engine’s coolant. We’ll have you on the road in no time. You can schedule service online or bring your car in at any time.

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