How Much Does a Radiator Flush Cost?

Your vehicle's radiator uses liquid called coolant to disperse heat from the engine into the surrounding air, allowing the radiator to operate efficiently—no small feat when it's generating plenty of power and heat under the hood. Over time, the radiator and coolant get dirty and are less effective at cooling. That's why you need a radiator flush every couple of years to keep your engine running smoothly.

What Is a Radiator Flush?

A radiator flush—also known as a coolant flush or cooling system flush—is a routine maintenance procedure that cleans your vehicle's cooling system while also replacing the old coolant. It's a more thorough process than a basic coolant change and helps prevent engine overheating and damage.

How it works

These are 4 common steps involved in a radiator flush:

• The old coolant is drained from the cooling system using a drain plug located on the radiator.
• A flushing solution mixed with distilled water is added to the cooling system. This chemical cleaner circulates through the engine while the vehicle runs for about 10 minutes; then the solution is drained.
• The radiator is rinsed using a flush kit, which pushes sediment and debris out of the radiator.
• The radiator is refilled with fresh coolant.
  Getting a radiator flush isn't maintenance that you should delay. If your cooling system isn't working properly, it can cause your car to overheat. So, not only won't you be traveling anywhere soon, but you may also end up facing costly engine damage.

Signs You May Need a Radiator Flush

In general, vehicles need a radiator flush every 30,000 to 100,000 miles. That's quite a range, so it's important to follow the instructions in your specific vehicle's owner's manual. Outside of mileage, here are warning signs you might need a radiator flush:

• Your engine is overheating—with a full coolant reservoir.
• You smell a syrupy odor coming from the engine.
• You hear engine knocking or unusual noises.
• You see coolant pooling under your vehicle.
• You spot visible debris or dirt in the coolant.

A flush at this point isn't just preventive—it could stop you from blowing a head gasket or warping the engine.

Average Cost for a Radiator Flush

On average, getting your radiator flushed at a mechanic will cost about $400 to $500, according to RepairPal. The cost of parts is about $270, while the rest of the cost is labor. Your specific cost will vary based on:

• Labor costs in your area
• Type of coolant your vehicle uses
• Your vehicle's make and model

If you're quoted a lot for just a flush, ask for a breakdown—there may be additional services included or your car might require specialty parts.

How To DIY Your Radiator Flush

If you're an experienced DIYer, you may be able to save money by doing a radiator flush at home. You'll still have to spend money on a flush kit (about $5), flush fluid (about $8) and fresh coolant for your engine, but you'll save money compared to visiting a mechanic. Here's an overview of how to flush your radiator at home:

1. Gather your supplies. You'll need:
   • A flush kit
   • Coolant, 1-2 gallons (check your owner's manual for the specific amount)
   • Safety goggles
   • Safety gloves
   • A collection pan for collecting dirty coolant
   • Distilled water
2. Allow your engine to cool for at least an hour. Only ever work on a cool engine.
3. Inspect the radiator, looking for any damage or cracks to the radiator or hoses. If you see any, consider bringing the car to a mechanic if you're not confident replacing the damaged parts yourself.
4. Install your flush kit by attaching it to the heater hose—the tube that circulates coolant.
5. Drain the coolant. Locate the drain plug on the underside of the radiator. Be sure to collect all the liquid in a secure collection pan. Replace the plug.
6. Fill the system with flush product and water. Only use distilled water, and follow the directions on the flush product you're using. Once the system is full, close the radiator cap.
7. Run the engine for 10 minutes to circulate the fluid. Then, allow it to cool completely.
8. Drain the flush solution by following the same steps you did to drain the coolant.
9. Rinse the radiator by pouring water through the radiator hose.
10. Flush the radiator hose by following the instructions on the kit to flush the hose.
11. Drain the system of all water by loosening the drain plug.
12. Refill the system with coolant. Bleed out any air by loosening bleeder screws along the system. Your owner's manual should indicate where they're located.

Used coolant is toxic and should never be poured down a drain or toilet or onto the ground. Instead, check with your local waste facility or auto parts store for proper disposal instructions.

Keep Your Cool: Maintain Your Cooling System

Your cooling system plays a critical role in keeping your engine running smoothly and safely. Staying on top of coolant levels and scheduling radiator flushes at the intervals recommended in your owner's manual can help you avoid overheating, breakdowns and expensive repairs down the road. The Synchrony Car Care credit card can help you pay for car repairs promptly, keeping you on the road and where you need to be. Learn more and apply now.

READ MORE: 15 Inside and Out Car Care Tips