Radiator Coolant Flush vs Drain and Refill

Has anyone done a coolant flush as opposed to just draining and refill? I've heard some of the flush maintenance can be damaging or unnecessary. Thanks for your advice!!

 

I have done just the drain and refill using Toyota 50/50 premix, if your coolant system is good and just want to freshen up the coolant, I do not see any problem with it. Now, If it was an older system with old unknown fluid, I would flush with distilled water, and then put in new Toyota 50/50 fluid.
Flush it using gallon jugs of distilled water, depending how bad the old fluid is, remove thermostat, drains, etc until it flushes clear water. I freshened up my 09 V6 at 100K.

 

Yes, flushed at 140K. No issues. Used Wallyworld's SuperTech, a universal coolant. No need to use corporate coolant. Also replaced hoses, belt, and thermostat.

Are you concerned new coolant could dislodge crud and plug the radiator? It's a valid concern if your cooling system has been neglected to that level. However, it's worse not replacing old coolant which will be lacking anti-corrosion and lubricating properties; neglected coolant will likely lead to cooling problems down the road.

 

No, I was concerned about using a flushing machine that some have said is not good for your vehicle. I ended up having it drained at a valvoline place. They used non toyota standard coolant and didn't take out all of the old coolant. I took it to a local mechanic who has worked on many toyota and he said that the toyota coolant is crucial because the additives are designed specifically for toyotas. he said he has had to fix many hoses because people use other coolant. Anyways, no way for me to know other than to take advice from others.

 

For systems where the condition is unknown I like to use a distilled vinegar flush (or citric acid + dIH2O) as it helps dissolve some of the scale distilled water misses. The Toyota LL coolant is also acidic but it just keeps the scale in suspension - flushing with a weakly acidic solution prior to coolant gets it out of there.

 

How strong a vinegar solution do you recommend? TIA.

 

I wonder if you are confusing a coolant flush with a transmission fluid flush?

 

I was wondering when this service should be done? Mine is still nice and pinkish and I never really saw a need to do this but lately I feel like I've reached 65k miles and may have to drain out the original coolant and put in some fresh stuff.

 

For me, it's not just about mileage, but time. I change coolant - radiator/block/overflow bottle at least every 3 yrs. regardless of mileage. I think Toyota's plan is 100K miles - 5 years.

My fluid/filter intervals occur more often than what the book calls for because I drive vehicles for 15-20 years.

 

What do you do with the old coolant you flush out? I know you can bring retired oil to an auto parts store for recycling but what do you do with coolant?

 

In my area O'Reilley's accepts all kinds of fluids.

 

In my area there is a household toxic roundup once a month in rotating cities within the county or you can take it to the household toxic facility on weekends.

If your city/county publishes a recycling guide check there.

 

I say phooey on the the Toyota coolant. Toyota specifies a P-HOAT (phosphate hybrid organic acid technology) type coolant for current models, back to mid 1990's. Specifically, a coolant with phosphate but no silicates, borates, 2-EHA, or nitrites - I might be missing a chemical there. The purpose of these chemicals is to protect the metals in the cooling system and inhibit corrosion.

Universal coolants are formulated to be compatible with a wide range of coolant systems. It's OK to trust the label of a reputable coolant manufacturer if they say their coolant is compatible with your vehicle - they wouldn't be in business if their product was snake oil. At 90K, I switched to a universal coolant (Prestone, I think) in our 98 Toyota Sienna. At 230K I had the water pump replaced as preventive maintenance - van has never had cooling issues. All my other Toyota products have SuperTech universal coolant. The important thing is to flush out the old stuff as much as possible. And to replace the coolant timely, as @Lester Lugnut points out above. Follow the manufacturer's instructions and you will not go wrong.

Using a flushing machine is OK. I think the issue is with neglected cooling systems where the flow of coolant caused by a flushing machine can dislodge matter that can get trapped in the water pump or thermostat. If the material is not flushed out completely, it acts as sandpaper as it flows through the coolant system, negating the anti corrosion properties of coolant.

http://www.aa1car.com/library/2004/us120426.htm

http://www.machinerylubrication.com/Read/841/coolant-fundamentals

http://www.engine-performance-onlin...l-antifreeze/engine-coolant-antifreeze-types/

 

https://youtu.be/s--5ft5YiHg

 

I disagree with removing the thermostat. If you do remove the thermostat, there's now no resistance in the cooling system. So all the muck and trash that sat in the bottom of the block breaks loose and floats up to the radiator clogging it!

 

Valvoline with Zerex. Meets all the requirements for both Toyota LLC and SLLC coolant and is red/pink in color. Not only is it a good replacement for the OE coolant, but it's also compatible with it.

Prediluted and ready to use.

$12 a gallon at Walmart. All the local stores in my area stock it.

 

I just did my engine coolant this past weekend at 150k miles. I had done one radiator drain previously.

This time I Drained the radiator and the two engine block drains. Replaced with Pentofrost A4 coolant, it is pre mixed.

 

Kinda funny they have Hyundai/Kia listed on there, when those come with green coolant from the factory.

I’ll give another thumbs up to Pentosin A4, you can buy it at Advance or Autozone.

 

It's antifreeze! They want you to think it's very special, only buy their expensive stuff. So now they got you thinking really hard cause it's a different F-----g color. I use walmart antifreeze without any issues!

 

The Zerex formula comes in different colors to mimic the OE colors...red for Toyota and blue for Honda and some of the European makes.

They list Honda and Hyundai/Kia on the red formula because they require a silicate free HOAT formula with phosphate, just like Toyotas do. Despite its red color it is compatible with Hyundai and Honda's OE fluid. You could use the blue formula in them too....including Toyotas.

BTW, not all green coolant is the same. Your basic green coolant is not the same as Hyundai/KIA's green coolant.

What ever coolant you decide to use, you're better off in the long run to go with a silicate free HOAT formula with a phosphate additive. Unless it specifically says that on the container....it is not.