How to Replace a Radiator in a Car

Keeping your engine cool is a tough job! Temperatures inside your engine’s combustion chambers can reach several thousand degrees Fahrenheit. While some of the heat escapes the engine with the exhaust gasses, it is the cooling system’s job to tame those extreme temperatures, which soak into the engine internal components themselves. Complex passageways route liquid coolant throughout the engine and out to a heat exchanger commonly known as the radiator. It’s the radiator that does the actual transfer of heat energy from the liquid coolant to the air outside your car. But, if that radiator isn’t able to do the job anymore, it is time for a replacement. Here’s how to replace a radiator in a car and keep your cool.

Why Replace a Radiator?

Radiators lead a tough life out in front of your dependable car, monster truck or family SUV. They need large amounts of unobstructed air, so they are placed right behind the front bumper and are really only protected from collision damage. That means road debris can sometimes get kicked up and damage a radiator, causing a leak. Other times internal corrosion can eat away at metal radiator parts, causing a leak from the inside out. It is also possible for plastic end tanks to crack after countless extreme heat cycles. Your radiator will usually last many years and even more than 100,000 plus miles, but when problems do arise, a replacement is like cheap insurance. Yes, there are radiator stop-leak products, but those are a temporary fix to get you home. 

How to Replace a Radiator

The following is a generic description of how to replace a radiator in an automobile. While the steps are mostly the same for all vehicles, there are always vehicle-specific procedures that you must follow. For vehicle specific instructions, it is best to consult a vehicle repair manual.

1. Disconnect the negative battery cable to prevent any accidental arcing or shocks while working under the hood.
2. Raise the front of the vehicle using your preferred method. A pair of drive-on ramps works fine, but you can also choose to lift up the vehicle using a floor jack. If you are using a floor jack, you must support the vehicle with jack stands. Never support a vehicle using a floor jack. A floor jack is for lifting only; a jack stand is for supporting. 
3. Set the parking brake and chock the rear wheels before sliding under the vehicle.
4. Let the engine cool for one hour.
5. Locate the radiator drain petcock, which is usually at the bottom of the radiator.
6. Drain the coolant from the radiator into a drain pan. 
7. Disconnect the upper radiator hose. 
8. Disconnect the lower radiator hose, taking care to capture any remaining coolant in the drain pan. Now is a good time to replace the upper or lower hoses if either feels mushy or swollen.
9. If you have an automatic transmission, you must disconnect the transmission cooler lines. Use a special flare wrench tool to loosen the connections and reduce the chance of damaging the connector hex. Prepare to catch any transmission fluid in a separate drain pan for recycling. 
10. Remove the radiator cooling fan.
11. Remove the radiator fan shroud.
12. Remove the radiator top mounting brackets.
13. Lift the radiator straight up and remove it from the engine bay. 
14. Compare the old radiator to the new radiator. They should have the same dimensions and the same connections. Oftentimes, replacement radiators will not look exactly like a factory OEM radiator, and that is okay because it will still fit and function like it.
15. Install the new radiator, taking care to transfer over any hardware, clips or mounting pads from the old radiator to the new radiator.
16. Reattach hoses, cooling lines and any other components removed to access the radiator.
17. Refill the radiator with coolant that matches the specifications found in your owner’s manual. 
18. Clean up any spilled coolant. Dispose of the coolant according to your local laws.

What About EV Radiator Replacement?

You may find it surprising that your electric vehicle may indeed have a radiator. Depending on the vehicle engineering, some of the onboard components are possibly liquid-cooled. Things like the battery, motor, inverter and control modules are possibly liquid-cooled. And, while not subject to the same extreme temperatures as an internal combustion engine, the radiator itself functions exactly the same. An EV radiator replacement is nearly identical to an internal combustion engine-powered vehicle, but may require highly specialized tools and safety equipment because of the high-voltage components. For that reason, we suggest leaving an EV radiator replacement to the experts.

How Long Does It Take to Replace a Radiator?

Wondering how long it takes to replace a radiator? That all depends on the vehicle. An older truck with lots of room to work under the hood and very few accessories may take only an hour. However, a modern SUV or minivan with a V6 engine sitting in a cramped engine bay could take an entire day. Replacing a radiator takes time to drain the coolant, remove the fan shroud and move any other components out of the way.

How Much Is It to Replace a Radiator?

So, how much does it cost to replace a radiator? That depends a lot on the vehicle and who does the work. An average car replacement radiator itself is $250 plus another $20 for fresh coolant, so a DIYer can expect to spend roughly $300 and a Saturday. That price goes up if you choose to replace any radiator hoses at the same time. Taking your vehicle to your local NAPA Auto Care, you can expect the average radiator replacement to cost anywhere from $1,000 to $1,500. Keep in mind that many components may need removed in order to access the radiator, which adds to labor costs. Check out the NAPA Auto Care Repair Estimator to get a better idea of the repair cost for your vehicle’s specific make and model.

If a leaky radiator is making you lose your cool, you can always head to your local NAPA Auto Care and let our ASE-certified technicians handle the problem. Not only will you get a top-notch repair, but it will also receive coverage by the NAPA Nationwide Peace of Mind® Warranty for 24 months or 24,000 miles.

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