Fixing an Antifreeze Leak Is Intermediate in Terms of Difficulty for Most DIYers. Here’s Everything You Need to Know to Fix an Antifreeze Leak at Home.
- DIY Difficulty Level: Intermediate
- Time Required: One to two hours
- Tools & Materials:
What Is Antifreeze?
Antifreeze is a type of fluid designed to help your vehicle’s engine run at an efficient operating temperature by preventing it from overheating or freezing. It’s a concentrated solution that comprises ethylene glycol and silica and turns into a coolant when mixed with water.
When your vehicle is running, the coolant circulates through the engine and picks up heat. Then, it returns to the radiator, where it cools and begins the cycle again. If you have an antifreeze leak, there won’t be enough coolant to keep your engine operating at the right temperature, which can cause a variety of mechanical problems.
Is It Safe To Drive With an Antifreeze Leak?
Even if your vehicle can still operate with an antifreeze leak, it’s highly recommended to get it fixed as soon as possible. Driving with an antifreeze leak can severely damage your engine, as you’re forcing it to run at harsh temperatures, which can result in overheating. If you allow the problem to persist, your car may break down and leave you stranded on the side of the road.
It’s essential that you don’t ignore an antifreeze leak because it can wear down or completely ruin certain components of your engine, including the connector rods, cylinder head, water pump, or head gaskets. Replacing these parts can set you back a pretty penny. Therefore, you should fix any minor leaks before they develop into significant issues that lead to costly repairs.
The duration, difficulty, and cost of an antifreeze leak repair can vary greatly depending on the severity and location of the leak. So, we suggest you first diagnose the problem before deciding whether it’s worth doing the repair yourself. If you’re dealing with a minor issue, such as a bad radiator clamp or hose, you should probably take matters into your own hands. But a major repair, such as replacing the coolant reservoir, radiator, or head gasket, is best left to a professional.
When To Replace Your Antifreeze?
Even if your vehicle isn’t leaking antifreeze, you should check the coolant level in your car at least twice a year. Over time, your antifreeze will become more electrically charged, which can corrode certain parts of the cooling system and triggers leaks. You can easily test your antifreeze yourself with coolant test strips or a hydrometer.
Regardless of your automobile’s coolant level and condition, you should replace your antifreeze once every 30,000 miles to keep your engine in good shape. However, the ideal interval may vary depending on your make and model, so it’s best to follow the recommendations in your owner’s manual. Alternatively, you can use the free FIXD app to find out the coolant change schedule for your vehicle.
What Are Common Symptoms Indicating You Have an Antifreeze Leak?
The following is a list of signs suggesting that your vehicle may be leaking antifreeze:
- Pink, red, blue, or green puddle under or inside your car
- Engine overheating
- Bubbling radiator
- White smoke
Keep in Mind
It’s important to note that there are several different types of antifreeze on the market. If you’re planning to fix an antifreeze leak yourself, make sure you use the right one when topping up your coolant. You can find out which antifreeze is best for your specific car make and model by checking your owner’s manual or consulting a professional. It’s also a good idea to flush your radiator system when you’re repairing an antifreeze leak.
How To Fix an Antifreeze Leak
Step 1: Locate the Leak
Usually, it’s relatively easy to locate an antifreeze leak as it tends to drip from beneath the engine compartment. Also, you may notice bubbles forming on a radiator hose connection or in the coolant reservoir. To locate the leak, start your engine and look under the hood to see if you can find any coolant flowing out. If you do, you can spot its source by tracing it.
Also, don’t forget to inspect the hose connections and other parts of the radiator for leaks. Keeping your vehicle running and turning on the air-conditioning system increase the pressure level in the cooling system. This heightened strain makes it easier for you to detect an antifreeze leak.
If you’re losing coolant but don’t see a leak, you may have to perform a coolant pressure test. A coolant pressure tester is a handheld tool that enables you to measure the pressure level inside the cooling system. If the pressure is low, it’s likely you have an internal coolant leak such as a failed head gasket.
Step 2: Fix the Leak
Once you’ve detected the location of the antifreeze leak in your vehicle, you can proceed to repair or replace the damaged part. For instance, if you’re dealing with a cracked radiator hose, the best way to stop the leak is to replace it. You should also check the hose clamps, which can loosen as a result of normal engine movement. Replace them if they’re worn out, and tighten them securely.
If the antifreeze leaks due to a major mechanical problem, such as a blown head gasket or broken radiator, it can be a complicated fix. You probably have to install a new head gasket or radiator, which can be expensive and labor-intensive. In this case, we recommend that you leave the job to a qualified mechanic.
Step 3: Finish the Project
To finish the project successfully, make sure you use the right antifreeze and replacement parts for your vehicle. Additionally, you have to properly dispose of the old coolant, as it contains toxic chemicals that can be life-threatening if ingested. Place the coolant in a large container and take it to a local recycling center or auto repair shop.
Still Need Help?
Want an expert mechanic on speed dial who can walk you through DIY repairs and answer any questions? Join FIXD Mechanic Hotline for unlimited access to our Master Mechanics from 8 a.m. to 8 p.m. Monday-Friday.

At FIXD, our mission is to make car ownership as simple, easy, and affordable as possible. Our research team utilizes the latest automotive data and insights to create tools and resources that help drivers get peace of mind and save money over the life of their car.