Best Radiator Flushes in 2022

Last update: January 11, 2023

Are radiator flushes necessary?

It's a common misconception that radiator flushes are necessary. In reality, they're not. Radiator flushes are only necessary if your radiator is filled with sediment. If your radiator is clean, there's no need to flush it.

Can I do a radiator flush myself?

You can, but it's not recommended. A radiator flush involves draining all the coolant from your radiator, and then refilling it with fresh coolant. It's a pretty simple process, but if you don't know what you're doing, you could end up causing serious damage to your engine. Plus, it's always a good idea to leave car maintenance to the professionals.

Can I put new coolant in with old coolant?

If your coolant is more than 50% full, you can just top it up with new coolant. However, if it’s less than 50% full, you should drain and replace the coolant completely.

Can you just drain and refill coolant?

If your coolant is starting to look dirty or rusty, you might be tempted to just drain it and refill with fresh coolant. But this isn't the best way to go about it. Draining your coolant also drains the rust and corrosion inhibitors that are crucial to protecting your engine. The best way to do a coolant flush is to use a flush kit that circulates fresh water through your system to remove all the old coolant.


Prestone AS110 Radiator Flush and Degreaser, 32 oz Review:


used in the badly clogged, oil cooler-failing 2013 Chevy Sonic. Oil cooler was replaced, Prestone Degreaser was added, and distilled water was supplied to complete the system. For around 30-45 minutes, the engine ran. Just enough time was given for the system to cool before the main pipes were detached to allow the system to drain. All peanut butter-like sludge seems to have been removed after draining. Making a second flush to boost your confidence.



Design Engineering 040206 Heater Hotter Performance Radiator Additive to Accelerate Heat Transfer, 16 oz. Review:


Our SUVs take forever to heat up, often taking 35 to 40 minutes simply to heat up, just like the majority of E70 BMW X5 2007 to 2010. I decided to give this a shot after having everything examined to see why it takes my heater so long to heat up, doing some research, changing the thermostat, flushing the system, and having two technicians fail to identify the issue. And I must say that it was successful. After using the full bottle, I had heat from the car in less than 10 minutes. So I can say that it went perfectly for me.



Niteo Motor Medic MF3 5-Minute Motor Flush - 32 oz. Review:


well-done engine cleaning I precisely ran the engine for 5 minutes and 30 seconds after changing the oil and adding the product. I was a little uneasy for approximately 30 seconds since the engine's higher cam area made an odd sound. On the dipstick, the oil changed from clear to light orange. The oil had a honey-like tint when I poured it into a jar, with a hint of the red dye that was packaged with it.The new oil used to turn light yellow after only a few miles of driving in the past. After the flush and another oil and filter change, I made a 20-mile drive. Still completely clear, the oil was.My SUV has 246K miles on it since I bought it new. Depending on the oil's color, I've changed my oil every 2,500 to 5,000 miles. Whenever the dipstick indicated dark brown, I changed the oil. mainly used 5W-30 conventional oil, but also occasionally used 0W-30 synthetic oil during the winter.A year ago, I did clean the oil pan. Back then, the oil pan gasket started to leak, so I had it cleaned and resealed.My experience with the product was excellent, however it seemed like regular oil changes had kept my engine reasonably clean. In light of this, I most likely won't flush it again till it has traveled 500K miles.



Gunk Motor Medic C1412 10-Minute Radiator Flush - 11 oz. Review:


It did a great job of clearing the clog in my car. I was able to remove all the crud that was causing my engine to overheat and produce a terrible clacking sound, but now I regrettably have a radiator leak. It is an older model GMC vehicle, and if it weren't for all the gunky residue clogging it up, the leak would have been there otherwise. The leak wasn't caused by the goods; it was merely old. The wonderful news is that the engine is running flawlessly once more—no more repulsive clacking noise. During the flush, I could actually hear a whistling sound, which told me whatever was clogged and causing the issue was being cleaned and opened up. I would definitely use again.I followed the instructions and began by draining the filthy, rusty, old, muddy water. I then flushed with clean water, added the flush product with hose water, and finished. The last drain drained clean.



HONDA MARINE OUTBOARD OUT BOARD BF75-BF130 NEW ATLANTIS FLUSH KIT Review:


Great results. The only issue is that the outboard does not create a tight seal, and some water leaks out the threads as a result. Possibly fixed by adding an O ring.



Irontite ThoroFlush (468-9110-16) Review:


I purchased this because the owner of my jeep before me had a poor water pump and poured an unbelievable amount of stop leak into it. In the five years since I've owned it, I've cleansed the system once when I changed the pump and twice with professional flushing, but the system is still full of stop leak. As nothing else was working, I thought I would try this. To my amazement, it worked quite well; my radiator coils are bright and shining, and my antifreeze is now green rather than brown. This stuff actually works. There are still a few brown droplets floating around in the antifreeze, but they are few and far between, and they will likely go away with the next flush. would most definitely suggest it to anyone who needs a thorough cleaning.



Permatex 80030 Heavy Duty Radiator Cleaner, 1 quart Review:


My vintage vehicle has been overheating to the point that I could only travel small distances in it. With limited success, I had already tried several cleaning solutions for the cooling system. Using the Permatex Heavy Duty Radiator Cleaner, a remarkable amount of "gunk" was removed from the radiator. I inserted a Gano Filter (autocoolantfilter.com) on the inlet hose after flushing the system numerous times with pure water. The Gano filter had captured an incredible quantity of debris after 150 miles after the cleaner had worked it loose. My Model A Ford is currently running smoothly.



Blue Devil Radiator Flush Review:


Wow! The effectiveness of this product exceeds my expectations! I recently bought a 1985 Cadillac Seville to restore. After draining the system, I made the decision to flush out the radiator in order to replace all the radiator hoses, heater hoses, thermostats, etc. Even though the antifreeze I drained appeared bright green and clean, I reasoned that it couldn't hurt. I used the Blue Devil bottle and water from the garden hose to fill the system. I drove the car 150 miles after letting it sit in the system for about a week (in the summer with no chance of temps dropping anywhere near freezing). When I drained the radiator, I was horrified to see that the water was dark brown and that the overflow tank contained brown muck! Throughout that week, I turned the heater up high to make sure the coolant was flowing through the heater core. I couldn't even tell if the heating was on at first. The following week, it started blowing fire! The water drained was unclean each time until the fourth time, when the overflow tank had no layer of brown sludge on the bottom and the radiator was once more draining clear water. I repeated this process three more times using only 100% pure water. I then replenished with a 50/50 mixture of Prestone antifreeze and the GM tablets they advise. Knowing that all of the corrosion and sludge in the cooling system was removed has given me much more peace of mind and possibly prevented future overheating and expensive repairs! My motor's coolant passageways were really cleaned out and opened up by Blue Devil. Now I'll apply it to all of my vehicles!


Do radiator flushes work?

A radiator flush is a process in which all the old coolant is removed from your car's cooling system and replaced with new coolant. Many mechanics will suggest that you get a radiator flush every 30,000 miles or so, but is this really necessary? The answer seems to be a resounding "no." In most cases, a radiator flush is simply not necessary. The old coolant in your system is not likely to cause any problems, and flushing it out will just add an extra step (and expense) to your car's maintenance routine.

Do you have to remove thermostat to flush coolant?

If your car is low on coolant, you may need to remove the thermostat to flush the system. The thermostat helps regulate the temperature of the coolant, so removing it will allow the coolant to flow more freely. You'll need to consult your car's manual to see if this is necessary.

Does Jiffy Lube Do radiator flush?

Jiffy Lube does not offer radiator flushes as a part of their services. Radiator flushes are a more specialized service that is not commonly offered by oil change services. If you are in need of a radiator flush, it is best to consult a mechanic or a specialist to get the job done.

How critical is a coolant flush?

Coolant flushes are a critical part of maintaining your vehicle. Over time, the coolant in your vehicle breaks down and becomes less effective at cooling your engine. A coolant flush removes the old coolant from your vehicle and replaces it with fresh coolant. This helps to ensure that your engine stays cool and operates at peak efficiency.

How do I know when I need a new radiator?

Your car's radiator has an important job to do. It helps to keep the engine cool by circulating coolant through the engine block. Over time, though, the radiator can become clogged with sediment and scale, which can reduce its efficiency. If your car's engine is running hot, or if you notice a coolant leak, it may be time to replace the radiator.

How long can radiator flush be left in?

If you are flushing your radiator to remove deposits, you can leave the flush in for up to 30 minutes. If you are using it to treat a coolant leak, you can leave the flush in for up to 12 hours.