There are a lot of things that you need to do to maintain your vehicle so that you can keep it running smoothly and keep any repair costs low. You need to do things like change your oil and the oil filter, keep an eye on your serpentine belt and your timing belt, get your brakes checked, and your tires rotated. Another bit of routine maintenance is to keep an eye on the coolant in your vehicle. You want to keep the coolant level topped up so that your engine doesn't overheat and cause some serious damage. But a problem a lot of people have is, with so many kinds of coolant available, can you use just any kind of coolant you want whatever you want? Is it okay to mix coolant? In general, the answer to that question is no.
There are many different kinds of coolant available for cars, not every kind is going to be formulated specifically for your vehicle. Let's take a look at the different kinds available and what they do.
Green Coolant
This is the standard, old school antifreeze that everyone is probably used to. It has a kind of bright yellow-green color to it that almost seems to glow. It also has a very sweet smell, and can be dangerous if it's left out. Animals in particular are really attracted to the smell of antifreeze. If you have a leak, or a container that they can easily access, it is not surprising to see cats especially try to drink it. Unfortunately, even a teaspoon of antifreeze could be lethal to an animal as small as a cat. Just a couple teaspoons could be enough to kill a human in fact.
Green coolant or antifreeze is made from something called ethylene glycol. To use this properly in your vehicle as a coolant you're going to want to mix it 50/50 with water in your radiator. It'll circulate through your radiator to the engine and back to maintain the temperature that you want to your vehicle to stay at.
Because of the danger associated with antifreeze you want to keep it away from children and animals at all costs. If someone were to drink antifreeze, or an animal got into it, there is actually a way that you can help them before you get medical attention. As weird as it sounds, vodka is a cure for drinking antifreeze. An alcohol like vodka is made of ethanol and ethanol counteracts the effects of ethylene glycol. When you're in a seriously dangerous situation and someone has consumed antifreeze, you could administer a small amount of vodka to help counteract the effects and then get them medical attention as soon as possible.
Green antifreeze is good for about 3 years or 36,000 miles according to the manufacturer. It's always good to check with the label on the kind of antifreeze you're using, and your owner's manual to see what works best.
Orange Antifreeze
Even though green antifreeze is the most common kind, orange antifreeze is also fairly popular. The difference between green and orange antifreeze is the life of the product. Orange antifreeze, often marketed as something called Dexcool, is still made from ethylene glycol but it has additional additives to increase the lifespan.
GM created the orange coolant known as Dexcool, and they recommend that you flush the system for the first time after 150,000 miles if you're using Dexcool. That said, it's worth noting that many drivers have had problems with Dexcool in the past. And there were even lawsuits filed that were settled as far back as 2008 relating to the effects of Dexcool on vehicles. This ended up getting Dexcool the nickname of DexKill.
In general, the point of Dexcool, if it's working properly, is that it has additional anti-corrosion additives in it that can increase the lifespan of the coolant and mean that you need to change it less often. It was how it was supposed to work anyway.
There are other kinds of orange antifreeze on the market that are not Dexcool, but they do share the color. OEM for instance has an orange antifreeze in their lineup which is just formulated to work in Chrysler, Dodge and Jeep vehicles.
Less Common Colors
Green and orange are hands-down the most common colors of antifreeze and are essentially the same thing; just one is meant to last longer than the other. In the last 20 or 30 years several other companies have begun producing formulations of antifreeze in a variety of colors. The colors are meant to coincide with different vehicle manufacturers and makes, but it can be very confusing for the average consumer to try to figure out the difference. Theoretically, some of these coolants could be mixed together because they are essentially the same, but, by the same token, some of them should never be mixed together.
Blue Antifreeze
There are a couple different blue antifreezes on the market that you can get right now. Some are a darker shade of blue and some are a lighter shade of blue. One of these formulations is specifically meant for Japanese automakers like Mitsubishi, Mazda, Nissan, and Infiniti. It's supposed to be an extended life antifreeze that's good for about five years of use and has anti-corrosion additives within it.
The other kind of blue antifreeze does the same job but it's meant for Acura, Honda, and Subaru vehicles. What's the difference between the two? Very little, other than the formulations have slightly tweaked amounts of the additives meant for anti-corrosion. In general, standard green antifreeze would work just as well in every single one of these vehicles, but just as some cars are designed to work with premium gasoline even though you can use regular, if you're looking for the best of the best you could use one of these premium formulations for your Infiniti, rather than the standard stuff. It's not really necessary though.
Yellow Antifreeze
Yellow antifreeze is meant to work with Kia and Hyundai Vehicles. It's an extended life antifreeze just like the blue, and it supposedly has a functional life of about five years.
Pink Antifreeze
There are two different kinds of pink antifreeze that you can find, one meant for European vehicles and one for Japanese vehicles. The Japanese formulation is supposed to work with Toyota and associated manufacturers like Scion and Lexus. Just like blue and yellow, and some extended life antifreeze and should keep your car running cool for a good five years.
The European formula of pink antifreeze which is marketed by OEM is actually in a purple bottle even though the liquid inside is pink. This is meant for Porsche, Volkswagen, and Audi vehicles. Again, the green antifreeze that most of us are used to would work just as well in any one of these vehicles. You don't need to use the special formulations in any particular vehicle.
Gold Antifreeze
There are a couple formulations of gold antifreeze as well, which is actually just sort of a rich yellow-orange colored liquid that could be mistaken for oil at a glance. One kind is formulated to work in Ford's family of vehicles, including the Lincoln and Mercury. The other kind of gold is a European blend that's supposed to work in vehicles like Mercedes-Benz, Volvo, BMW, jaguar, and the mini.
All of these colored blends of antifreeze have anti-corrosion additives, and supposedly there's been designed to work specifically with the components and the kind of metal that was used in the particular vehicle that it's been assigned to. Some mechanics will tell you there is literally no difference between using this antifreeze or your standard green antifreeze other than the fact that they do have a longer life. But by that same token, you could use an orange brand of antifreeze like DexCool or something that has a better reputation and get an even longer life without being worried about it.
It's best to consult with your owner's manual to see what kind of coolant it recommends for your vehicle. At the end of the day, the manufacturer is going to have the absolute best recommendation for your vehicle.
Mixing Coolants
At the end of the day, the orange and the green coolants are the most common kinds. So, if you have green antifreeze in your radiator right now, is it an okay thing to top it up with some orange antifreeze in the hopes that it will last longer? The answer that is a solid no.
Even though green antifreeze and orange antifreeze or both made from ethylene glycol, it is the additives in the orange antifreeze that make it incompatible with green antifreeze. You cannot mix these together because it could potentially cause a lot of damage to your vehicle.
What happens when you mix green antifreeze in orange antifreeze is that the mixture actually begins to coagulate. Rather than a smooth-running liquid, you're going to end up with a syrupy kind of jelly-like substance. As you can imagine, if the coolant in your vehicle becomes thick, it can't run smoothly from the radiator to the engine in back and keep things cool the way it's meant to be. This can end up causing some serious damage down the line if your engine begins to overheat.
Overheated Engine Problems
If you continue to allow your vehicle to run without proper coolant, either because you don't have it off or perhaps because he's mixed it and now you've got that thick and syrupy mix of coolants, you're risking an overheated engine. You never want your engine to run hot. Well it doesn't sound like a big deal; it could lead to some of the most expensive and serious repairs that any car has to face.
Warped Cylinder Heads: The cylinder heads in your vehicle are probably made of aluminum, which can only handle so much heat. If your car continues to run too hot, the cylinder heads get Warped. That's going to cause a lot of engine misfires and can potentially lead to a broken head gasket.
Broken Head Gasket: If you blow the head gasket in your engine, the coolant in the oil are going to start mixing and essentially you have just killed your engine and potentially the transmission as well. You'll be seeing smoke coming out of the vehicle, and the fixed will very likely be rebuilding the engine entirely. This repair could cost you thousands of dollars to take care of.
Damaged Hoses: When your car is allowed to overheat, the coolant itself will boil and expand as any liquid does. This could build up pressure within the hoses and cause them to explode and detach from your radiator or your engine.
All of these engine issues bring big repair bills with them. They're also very time-consuming, and they mean you're going to be without a functional automobile for a while. Not a lot of people consider things this far ahead when they're looking at mixing one kind of coolant with another. It really seems like it shouldn't be that big of a deal, but obviously it is.
The Bottom Line
If you're looking to switch up the coolant in your vehicle from orange to green, green to orange, or any of the other colors that we've mentioned for whatever reason, you need to flush the system. It's the safest thing to do, and the best way to ensure that you're not going to damage anything in the vehicle and end up getting a massive repair bill as a result.
You can handle a coolant flush on your own if you want to try to take on a DIY job yourself, or you can simply let a professional do it at the shop. If you're in the market to do it yourself, there are a lot of videos on the internet that can walk you through the process so that it can not cause you too much stress, and you'll save yourself a few dollars by doing it yourself. If you're not comfortable doing it, it's also a fairly simple process for a mechanic to do on your behalf, either way, you need to make sure the whole system is clean before you put a new antifreeze in the system to avoid the issues that we've already mentioned.