Do Cars Use More Coolant In The Summer?

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Since the weather is too hot, which literally means that liquids would evaporate faster, would my car need more coolant?

It is very necessary that a vehicle does not run out of coolant, asides from leading to overheating, driving on an empty coolant is not good for the engine. But do cars use more coolant in the summer?

In every car, the coolant is enclosed and further covered with a bonnet; it does not come in direct contact with sunlight to trigger rapid evaporation of the liquid/antifreeze poured inside.

However, due to the high impact of sun and heat generated by the engine, the temperature may rise inside the engine bay, causing the thermostat to open frequently to allow coolant penetrate the engine; this may cause more consumption of the coolant liquid.

Do Cars Use More Coolant In The Summer?

Do Cars Use More Coolant In The Summer

To further explain what’s hinted above, when driving on summer days, your engine would naturally heat up very fast due to the high impact of the scorching sun. The thermostat valve in the engine area helps to regulate the temperature inside the engine.

When the temperature is too high in the engine, the valve opens up to allow the liquid from the coolant reservoir to enter the engine, while hot steam from inside the engine passes through the valve’s opening onto the radiator and then gets blown away.

Apparently, during summer, the thermostat valve may open up frequently than it would do on winter days. Thus, more coolant will be consumed by the engine to maintain regular temperature and avoid overheating.

That said, it is liable that cars could consume more coolant in summer than they’d do in winter. More so, it is advised, by some auto experts, that you should mix the coolant with water in a 50:50 blend. This implies that the coolant should be 50% while water is 50% in the mixture.

Filling the reservoir with this coolant blend helps to avoid overheating and somehow reduces the amount of coolant you use in your car during summer.

However, because it is advised by some experts to run on a 50/50 coolant blend doesn’t mean that you should consider using only water in a bid to save coolant.

Water isn’t good for your engine, and while it can be much effective in cooling down your car faster than coolant, water does not contain any anticorrosive additive to save your engine from rot.

Mixing Coolant With Water vs Using Straight Water In Summer

If you’re concerned about spending more on coolant during the summer season, then you can consider mixing your remnant coolant liquid with water in a 50/50 solution. It is safe to use mixed coolant in your car during summer, but it’s not advisable during winter.

Also, you should ensure that water does not exceed the actual coolant liquid to avoid rot in some metal components in the engine bay. Interestingly, there are premixed coolants sold in auto shops; you can buy these ones to avoid making mistakes when trying to mix coolant with water.

In contrast, it is very dangerous to use only water as a coolant liquid for your vehicle. Doing so can lead to total damage to the engine and would cost a whole lot of money to repair. You may even end up having to replace the entire engine or getting a new ride.

Using straight water will introduce rot, which would lead to the decay of important components in the engine bay. More so, water tends to evaporate very quickly when left in a severely heated environment.

Simply put, antifreeze/coolant liquid is designed to cool down vehicles without evaporating and contains anticorrosive additives. But, water includes no additives and would evaporate once the engine gets hot.

Read Also: Normal Coolant Temperature for a Car


Do cars use more coolant in the summer? Literally, they do, but not as much as it may sound. In contrast, you can resolve to use premixed coolant liquids – they are quite cheaper to afford. But, don’t attempt to run on straight water irrespective of the reason you’d want to give.

Furthermore, always check up the car every morning to ensure that the coolant is filled, oil is present, and other stuff are in good condition. This pre-check can help to prevent overheating in summer days. Hope we answered your question?

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