How much coolant does a car have?

Coolant is an important fluid that keeps your car running smoothly. When the time comes to top off the system or perform a flush, you want to know – how much coolant does a car hold?

The type of car you have will determine how much coolant is needed. The average vehicle holds between one to three gallons. However, it is possible for larger vehicles, such as trucks and SUVs, to have more. Check the owner’s manual to determine the appropriate amount for your vehicle.

This guide will explain what engine coolant does and how to use it. This guide will also explain how to top-off the engine, how the coolant differs from antifreeze and how you can get it to work.

What exactly is Engine Coolant, and how can it help you?

Your car’s engine coolant is the fluid that moves through the cooling system to remove heat and ensure the motor works at normal temperatures. This is a difficult job, considering your engine can withstand temperatures up to 200°F.

Fluid is transferred from the radiator to the engine. The fluid absorbs heat from the engine and then cools down through the system. After cooling down, the fluid can flow through the engine again to heat dissipating more heat. 

The Function of Coolant

High-quality coolant is important for many reasons. These are three major purposes for this fluid.

• Removes heat from the motor and raises the boiling point of the fluid higher than what’s normal.
• Reduces the freezing of the liquid when temperatures go below 32 degrees Fahrenheit by lowing the freezing point so the engine block doesn’t crack and break. 
• This prevents corrosion of the engine, radiator, and heater core. 

Coolant might not be discussed as much as engine oil, but it’s just as important as an automotive fluid. Engine failure could occur if there isn't enough fluid. 

RELATED: 10 Best Engine Coolants & Antifreeze – Review & Buyer’s Guide

How to Turn Off Your Engine Coolant

1. Park Car

The car should be cool before you start working with the coolant. The heat can cause serious injuries and is potentially dangerous.

Place your car on a level surface. You should leave the vehicle parked on a flat surface if you are driving it until the engine cools down. 

READ MORE: Antifreeze for your Car (7 Steps).

2. Locate Reservoir

It is important to determine the location where the coolant can be pumped. You can look in the owner’s manual for more directions for your particular car model.

A clear plastic container with a brightly colored liquid in it is what you are searching for. The reservoir will have a MIN/MAX line that indicates how full the fluid is. If coolant level is less than the MIN, add fluid. 

3. Coolant

Mix the coolant well before you use it. To make things easier, you can buy pre-mixed coolers. However, these coolants are typically more expensive long-term.

Follow all instructions provided on the package to mix the coolant. Also, it’s very important that you use the right coolant type for your vehicle. Fill the cooling system with the same coolant that's already in it if you want to top off. Mixing two different formulations can cause a chemical reaction that could lead to a disastrous outcome.

If you aren’t sure what the differences are between coolant types, we will discuss that more in a minute. If you want more information, we will help you distinguish between coolant or antifreeze. 

RELATED: Is it possible to mix different types of coolant? (Which Types?)

4. Fill to MAX Line

Pour your mixture coolant in carefully. Be sure to pay attention where the MAX line appears.

You should stop filling the reservoir once the coolant has reached the MAX level. Clean up spillages and seal the reservoir. It should now be ready to use. 

There are 3 types of coolant

1. IAT

This is one the oldest forms of coolant. You won’t find this type used in modern cars today because there are options that are more effective. IAT is an acronym for inorganic additive tech and it's slowly being phased out.

You will need to flush your vehicle's IAT cooling system more frequently if it is older than the rest. It should be changed every 24,000 miles or two years on average. Your cooling system could fail if it is not replaced regularly. 

2. OAT

OAT coolant has become more popular since 2000. OAT stands to represent organic acid technology. It is mainly used for GM vehicles. 

This coolant will last you much longer without needing to be changed. On average, it shouldn’t need to be changed until your car hits 150,000 miles or five years lapse, whichever comes first. This allows you to save money on regular maintenance and also helps your car last longer. 

OAT coolants can be colored in either orange or red. The fluid's fully neutralized acids make it completely anti-corrosive, providing maximum protection. 

3. HOAT

There’s also the option to use HOAT coolant. Hybrid Organic Acid Technology stands for HOAT.

It’s most comparable to the OAT coolant that we previously discussed, so it has a replacement cycle that is similar. You can find HOAT cooler in many colors depending on its formulation. 

READ MORE: WHAT IS HOAT COOLANT? – Function & Difference vs OAT

Comparison of Antifreeze and Coolant

If you are around the automotive world for any amount of time, you’ll hear the words antifreeze and coolant used interchangeably, even though they are quite different. These are not the same formulations and shouldn’t be used in place of one another. 

Coolant for engines is the fluid which circulates throughout the engine in order to maintain the proper temperatures. Coolant is a solution that’s designed by mixing several other substances together. This coolant is pre-mixed and contains antifreeze. It is also possible to purchase concentrated antifreeze and make your own. However, this shouldn’t be done by anyone that isn’t experienced. 

An antifreeze liquid is chemically based. It’s made from ethylene glycol, which is also found in the pre-mixed coolant formulations that you put in your vehicle. It can be purchased straight or mixed with the right amount of water. You should only funnel the product into your car's cooling system after you have verified the correct composition. 

You have basically two choices. Pre-mixed solutions, also known as coolant, can be purchased. This formula is going to cost you more because it has water mixed into it, but it’s the easiest option to use if you aren’t experienced. You could also use a container of antifreeze to mix with water and make your own coolant. It is important to always check the label and read every instruction as each brand may have different requirements. 

Both the coolant and antifreeze formulations can be toxic. All bottles should be kept out of the reach of children and pets. It can be sweetened, which makes it attractive to those who are vulnerable. Additionally, it’s important to dispose of old coolant and antifreeze properly.

Coolant FAQs