Your Antifreeze/Coolant Questions Answered
It might seem like antifreeze should be used in cold weather and coolant in warm weather, but antifreeze is a type of coolant. No matter what coolant your car uses, figuring out the right one for your car and the right amount to keep in the tank in cold and warm weather are critical to your engine's cooling system. Before you add anything to your coolant tank, let’s take some time to answer common questions that people ask about the stuff that keeps your car’s engine running at just the right temperature.
What Kind of Engine Coolant Should I Use?
Most basic antifreeze formulas are interchangeable, and very few vehicles have hard requirements about what they require. You should check your owner’s manual, though, because most car manufacturers do recommend certain formulations for peak performance. Of course, there are also cars that require a special coolant formula too. They might be less common, but GM owners will find certain models require DEX COOL® and no other type.
Of course, there are specialty formulas available, and understanding the options there could make your car ownership experience a lot better. Some examples of special variants you might find useful under the right circumstances include:
- Cold weather protection to -34 degrees is available from many manufacturers
- Antifreeze that is non-toxic to animals is also very popular
- Some coolant manufacturers offer extreme heat formulas similar to their cold weather options
In the end, as long as you are choosing a formula that is compatible with your vehicle, what antifreeze to use is largely dependent on your needs.
What Kind of Coolant Does My Car Need?
If you are still unsure what to pick, the best starting point is to buy the coolant recommended in your owner’s manual. If you check the brand’s variants, you can probably find the variants discussed above. If you need a special formula, the manual is also your best bet to learn which one, too. If you don’t know where the manual is and you need to know, AutoZone can help: either ask a store associate or use our coolant lookup to find the right kind for your vehicle’s make and model.
Back in the day, coolant and antifreeze was considered non-application specific, meaning that there was not a specific antifreeze for a specific car. While manufacturers had different requirements, you could easily see which antifreeze was required by matching the color of the new antifreeze with the old antifreeze as they were not specific to the manufacturer. Newer cars have more specific formulations to meet the needs of modern vehicles, meaning these vehicles need application specific antifreeze, which is the right OE-type of coolant.
Are Basic Antifreeze Formulas the Same?
Almost every antifreeze chosen by OE designers is 95 percent ethylene glycol, but the additives vary a lot from manufacturer to manufacturer and provide each brand and variant with its unique characteristics. With a few exceptions like the GM cars that require DEX COOL formulas, this makes them compatible. The practice of following the recommendations is one of using the antifreeze that tested best under controlled conditions.
How Often Do I Need To Change My Coolant?
A full coolant replacement is generally recommended every year or two by manufacturers, depending on the model. Sometimes this is phrased in mileage, but it usually calculates to the average driven over a couple years. You can check the specific gravity and color of your coolant to see if it is time. You’ll need a test kit to do it yourself. Most of the time, coolant is good longer than the estimate in the owner’s manual, but sometimes it breaks down early and you lose performance. That’s why regular checks on the coolant will serve you better than an estimate in time or miles. You can get a longer lifespan out of extended life varieties, with some formulas boasting life expectancies as high as five years. If you are curious about extended life varieties, check out whether your manufacturer has made any recommendations about a maximum life formula in addition to the OEM one.
Do I Need To Add Coolant Regularly?
In an ideal world, no. Theoretically your coolant system should be self-contained, reusing the same fluid until it breaks down enough you need to change it. The way things usually work, though is that the system has an overflow tank for a reason, and sometimes it overflows. If the level is slightly too high at a a normal temperature you should be fine. If you’re in extreme heat and temperatures get slightly above optimal, you could also lose coolant you normally depend on due to volume changes.
Checking the coolant on a regular basis will tell you whether you need to add it, as well as how well it is working. Most people will find they only rarely have to add coolant when a vehicle is new, but as cars age many start to have lower efficiency cooling systems. Preventive maintenance and good upkeep in general can both help slow down this process, and a full vehicle restoration can turn back the clock if you are dedicated to preserving a vehicle.
Does Antifreeze Do Anything Else?
Yes! Antifreeze is a vital lubricant for the car’s water pump, and it also helps prevent against corrosion in the vehicle’s components. That’s why you should always use the mixture recommended in your manual, and why it’s important to keep the coolant at optimal levels.
The Car Is Losing Antifreeze? Is There a Leak?
There are many reasons a vehicle could lose antifreeze, including overflow and evaporation if a cap is loose. If you lose a steady amount of coolant regularly and you can predict about how much you need each time you check your vehicle, then you probably have a leak and are not experiencing typical coolant loss. If you want to find where you’re leaking from, a drop cloth under the vehicle can help pinpoint the leak because it will show a stain where the antifreeze drips. If you don’t see a drip, you could have a leak at a point where it only leaks when the car is functioning.
Consulting a professional for hard to pinpoint leaks can save you time, but coolant system diagnostic guides are out there for the dedicated do-it-yourself enthusiast. Remember to follow all the manufacturer’s recommendations for replacement, including the replacement of hoses and valves at the recommended times. This will help prevent leaks from developing, and it’s much easier than troubleshooting the system for a bad seal or a leaky hose. The best part is, refreshing the system will help it hold on to that efficiency new cars have, so it’s easier to ask your engine to perform at a higher level for longer.