The importance of coolant flushes

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So I just got my LC back from my mechanic. I would have done the work myself but he is a knowledgeable Toyota guy and given my LC is a rust country sweetheart, I'll let him deal with the rust.... not to mention I am in the process of selling my place and all my possessions.

ANYWAYS.... When I dropped the LC off the coolant was brown. The overflow bottle was brown, the overflow hose was clogged with sand resulting in coolant overflowing the pressure cap. It was bad....REALLY BAD. According to my scan gauge I was running about 195-205F

Now, thanks to IH8Mud and the paranoia set in about poorly maintained coolant systems, headgaskets etc I figure that if the HG was going to blow...It would have with the heat and added pressure.

I replaced the waterpump, fan clutch to blue, new tstat, PHH, all other hoses, and switched to green coolant. Apparently when the block was flushed it took 8 full flushes with cleaner to come out clear. The mechanic said he had never seen a coolant system so absolutely nasty in 30 years. I asked him about the radiator and he said it was spotless....odd.

It's now running at 185-190

So...planning on an annual or bi-annual flushing now...
 
I flushed mine a few nights a go and nothing really came out. I'm kind of worried about that. The coolant that drained out looked nasty and I know the po didn't really maintain it properly. I was expecting a chunky brown geyser to shoot out, but it was pretty clear.

Annual flush is super mud ocd lol. Your cruiser probably made it 20 years without being flushed. Antifreeze doesn't break down that fast. You could do another one in the next year just to see if anything else got knocked loose, but I wouldn't bother doing it until like 5 years.
 
Sounds nasty. It's weird that people would buy such expensive trucks and neglect them. Mine wasn't too dirty but after changing the pump, t-stat & blue clutch it's pretty much impossible for me to break 187. It used to regularly go to 205 like yours.
 
Yep just flushed mine and put in new oem radiator from Toyota, I was running 200-205 nor hottest it gets is 193. Old radiator looked bad don't think it had ever been flushed.
 
I flush once a year. Coolant is cheap.
 
Ounce a year in the spring.
 
Every 5 Yrs here, never had issues. Had 3 close or over 200K.
Going Prestone Green in all. Currently they are Toyota Red, but that is getting Lexus Expensive.
 
Yep, hate to admit it but I am going Green next time as well. The local Toyota dealer quoted me $43 for a gallon of red on the last visit. I stomached it at $27 a gallon but I don't see how the return on investment could be worth 8x green.
 
When I baselined my coolant system, I actually installed a flush kit into the heater hose on the firewall. That way I can easily flush the system from top down. My truck runs about 5-10 degrees cooler after baseline as well.

And as for green vs red, I think the general consensus is that either is ok, as long as you don't mix them. Assuming that, green is the best option since its cheaper and can be had easily anywhere in the case of an emergency.

@The Raven, is it possible that the PO might have mixed green and red, thus the system being in such bad shape? just a thought.
 
When I baselined my coolant system, I actually installed a flush kit into the heater hose on the firewall. That way I can easily flush the system from top down. My truck runs about 5-10 degrees cooler after baseline as well.

And as for green vs red, I think the general consensus is that either is ok, as long as you don't mix them. Assuming that, green is the best option since its cheaper and can be had easily anywhere in the case of an emergency.

@The Raven, is it possible that the PO might have mixed green and red, thus the system being in such bad shape? just a thought.


^^^^^^^^^^^ Yes, I installed a flush kit on my Cruiser 15 yrs ago. Makes it much easier to clean the system.

I stopped using Toyota Red some years back when it got just stupid expensive. I've been using Zerex Asian with good results:

Antifreeze/Coolant Zerex 675130 - Engine Coolant/Antifreeze | O'Reilly Auto Parts

In fact, I am getting ready to flush the system this weekend.
 
My local O'Reillys sells premixed Zerex Asian formula coolant at $14.99 per gallon, so you'll need a bit over 3 gallons to fill a FZJ80 cooling system. That works out to be $45 coolant cost. If you need to top it off you'll need a spare gallon for that, add $15.

At a local Toyota dealer, without a discount, they charge $24.99 for a gallon of undiliuted 100% Toyota Red coolant.

So if you use Toyota Red 100% coolant (2 gal = $50) mixed at 50:50 with distilled water ($5) it will cost you $55 for five years. Plus you will have some 100% coolant left over if needed for topping off during that same time period.

If you change out the Zerex every year for five years you will have spent 5 x $45 = $225 over that same time period.

So you could end up spending four times as much for the non-OEM coolant compared to the Toyota Red. If you run the non-OEM brand coolant for the same length of time as the Toyota Red the savings is minimal, $55 versus $45 over five years, but then there's the question whether you'll get the same level of protection with the aftermarket coolant?? IDK.

FWIW.
 
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I think using consistent coolant and taking some measures to maintain the system is a good idea. That said, these are tough boring engines without a need for white glove treatment. I think a lot of people are overthinking this.
 
Just for s***s and giggles I checked for the red coolant in Newfoundland.....it was not there. I did in Lab City, Labrador....same result. Point being....Green is everywhere. Use what's available where you go. For me...that is green :)
 
I think using consistent coolant and taking some measures to maintain the system is a good idea. That said, these are tough boring engines without a need for white glove treatment. I think a lot of people are overthinking this.

They are. But they are also 20+ year old tough boring engines. I'd like mine to last another 20+ years. If that means wasting a few bucks each year, I don't mind.

I don't golf. I don't drink. I gotta have some vice for crying out loud!!
 
Six year old, 50,000 mile, 50/50 mix and a two week old approximately 10% mix.

I did just swap out the radiator because it was leaking at the top tank but it looked very clean inside.

Maybe I should flush more often.

Compare.jpg
 
What's a "coolant"? Is it as important as a cup holder?
 
What happens when you mix red and green, anyhow?

Nothing in my case. I added a transmission cooler to my Tacoma not long after I bought it new in 2001 which resulted in a bunch of the coolant (red) draining. I added green back to fill it back up (not knowing any better). You know what happened? Nothing. I sold that truck in 2013 (about 10 years after I mixed red and green) and the cooling system/radiator/etc. was perfectly fine.
 

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