Ideal coolant ratio?

Time to nerd out again. I'm going to replace my upper and lower radiator hoses soon (likely the originals) when I flush my coolant. The coolant is not at the 30k interval yet, but I'm close to two years. I'm using the Toyota Red concentrate and mixing coolant with distilled water.

Last time I flushed it I went with a 60/40 mix, 60% coolant, at the recommendation of the Toyota parts department. Mind you I live in Sacramento CA. Doesn't ever get too cold here. I did drain the block, had the heater dial all the way to hot, and did 2 or 3 flushes with distilled water before the final fill. Purged all air, etc.

This time, after some research, I'm thinking of a 50/50 or even a 40/60 with only 40% coolant. Reason is, during the summer months it gets pretty hot here and my ScanGauge 2 reports coolant temps of up to approx 209F, higher than I'd like. *Jiggle valve orientation of thermostat is unknown because I didn't install it. With more water, I should see lower temps...

Any Sacramento taco drivers know what coolant ratio you're running? Or thoughts in general from people not located in my area?

Thanks everyone!

 

if 209 scares you, you should see my sport bike when I'm sitting in traffic. It often goes above 225F and the fans kick on. More water will only decrease the boiling point. Not sure how much boiling point reduction you get when an increase in water.

 

50/50
too much water cause corrosion

 

IMO, you are overthinking this. I'm not convinced there is any real evidence that shows more water will lead to any significant change in operating temps. 209 isn't really that hot.

You might be suffering from what I like to call Scangauge Syndrome (trademark). It's where you are able to precisely track small, yet more or less insignificant changes in temperatures or other data.

I'm generally of the school of thought that if your temp light didn't come on, you are well within the design specs the engineers set for the motor, and don't need to worry that much.

I, also in Sacto, just run 50/50, premix.

Technically, it's not "coolant" but anti-freeze that you are mixing with the water. Corrosion might be one reason to add anti-freeze, but the main reason is, well, to not let it freeze. Colder temps and you might want to go to a 60/40 or something, but I see no reason to go with anything buy 505/50 in Sacramento.

When it's under pressure, I don't think any change in the boiling point matters that much.

 

Pure water does cool better than any amount of anti-freeze.

Racers swear by that. (plus tracks don;t want slippery coolant on the track but still, they say it)

 

Sure, in racing conditions where you're riding that fine line between max power and blowing it up, sure, a few extra degrees will surely help. I just don't see it being a big factor in street engines for everyday use.

This is a case where I generally defer to the Toyota engineers who design the motors to run at a certain temp, and the cooling capacity is such that having a coolant that "technically" cools a few degrees better likely doesn't really matter.

This was a pretty interesting read, and the reasons they state are all over the board.
https://www.quora.com/Why-do-racing-cars-use-only-water-as-coolant-and-not-antifreeze-water-mix

 

This is my first Tacoma-although I did have an old Celica that I miss. And I am amazed at the large size of this 3rd gen radiator. I guess a thread hijack - but relevant. This is an important topic here in Montana - in Cali I wouldn’t worry about it.

 

Where’s your data to back up your claims about water?

Ethylene glycol antifreeze is banned from every racetrack I have ever been on. BANNED. The reasons are because it is extremely hard to remove or neutralize. Yes it is slippery but so is oil. Oil however can be cleaned using cement dust but ethylene glycol can not.

On a base level water is better. But that only lasts until corrosion sets in or you pump fails. Antifreeze includes corrosion inhibitors and lubricants for your pump. No one on any racetrack uses straight water. Everyone uses some sort of pump lubricant which usually is part of a water additive that also increases heat transfer.

If the OP needs more cooling use 50/50 and add Redline water wetter. Remember these are chemicals that behave based on their ratios and water wetter did extensive testing that proved that their product will operate best at a certain ratio. More water wetter actually reduced its efficiency so read and follow the label. Water wetter claims to increase heat transfer. So the cylinder / block transfers more heat to the coolant which takes it away to the radiator which then transfers more heat to the aluminum and then to the air. I personally have been using it for decades and it does work. I had one motor that would overheat regularly. With water wetter mixed properly it would stop overheating except for the most extreme scenarios. I think the bottle claims a 20degree drop in coolant temps due to increased efficiency.

 

The 'coolant' part of your coolant is there for 3 reasons: lubrication for the water pump, anti-corrosive, and protection against freezing. The 'water' part of your coolant is there for cooling. The *radiator cap* is there for boiling protection, because science and something neat that happens to liquid boiling points when pressure is added. 60/40 antifreeze/water is suggested so the stealership can sell you moar coolant. 50/50 is better. In my autocross car I ran 20 coolant/80 water with water wetter because nothing heat soaks your turbocharged engine faster than sitting on 120 degree tarmac at idle while waiting in line to start for 20 minutes. For a 42 second run. Fuck I'm glad I gave up on auto-x. Will 40/60 coolant/water cool better? Yes. Science says so:
https://www.hotrod.com/articles/glycol-or-water-coolant/

As for the above, IMHO no water wetter is needed at 50/50 or even 40/60: it's primary purpose is to provide lubrication that a pure water system lacks. Not, as they claim, to 'decrease the surface tension of the water so as to aid in heat transfer' which is marketing shitfuckery. Lubricant. Primary purpose.

 

So you have a PHD in I don’t believe you. Almost as powerful a degree as the PHD in because I say so.

I agree 100% in the lubrication aspect of Water Wetter. But I also have experienced the improvement due to it in both my street and racebike. Let’s take my street bike as an example. It has side mounted rads which work well when moving at 80kmh or better. Anything below this and there isn’t enough negative pressure to pull air through them. I tried the carbon fiber fins that were supposed to make a difference. They look nice but not enough difference with them on to argue they have any effect. Now water wetter reduces the number of times the fan comes on and reduces the time it takes for the fans to drop the coolant temp below the threshold that the fans activate. Add similar results in cooling to a half dozen racebikes, a diesel tractor with a cooling issue and my list goes on.

 

HA! Yeah, I was getting a little salty last night. The only cooling benefit I've seen personally is due to the higher ratio of water in the system. If you achieved better cooling with no change anything else then kudos to you, but I'm not the only one who has logged data to see almost no change in temp sensor output before and after installation:
https://www.thetruthaboutcars.com/2008/01/redline-waterwetter®-review/

 

I live near and work in one of the hottest cities in the country. Bullhead City, AZ. I just use 50/50. No overheating, even though my commute home is up 12 miles of 6% grade. Sometimes temp is over 120 when i leave work.

 

50/50 is optimal for most teperatures. Changing the ratio a little either way won't hurt or benefit you in California weather. Your radiator cap should bring the boiling point to about 220. 209 is pretty hot for oir trucks though, might want to check your fan clutch or see if the rad is plugged with dirt or the fins are bent. This engine should run about 180 even in 100 degree plus weather.

Edit: may want to change your thermostat too. Cheap insurance.

 

180? That seems pretty cool...I usually sit at 190 or maybe 186 if it's a cool day, don't think I've ever seen it under 186 though when fully warmed up. I agree though that anything near 210 is too hot unless you're towing, 4x4'ing, driving through Death Valley in the middle of summer, etc.

edit: just saw you have a 2012, maybe the 4.0 runs a bit cooler than the 3.4

 

Yeah I was generalizing, 180-190 is about right

 

I didn't even realize OP had a 1st gen lol. But still 209 is a little warm

 

Going to agree with @jbrandt about the scanguage syndrome. I see what you're getting at but don't over think it. Just use the Toyota pre-mix instead of the concentrate and move on to the next item on the to-do list.

 

Don't forget to change the radiator cap. Over time they get weak and don't hold pressure like they should which can compromise the ability of the cooling system to do its job.

 

Yeah even when wheeling in 4lo with the AC on during summer I don't typically see anything over 205 and that's only when it's really hot, I think having a manual transmission helps though. Almost everyone I've wheeled with that ends up with overheating engines/transmissions has an auto.

I did see temps in the 210+ range when I first got my truck a few times in the summer and would have to pull over and let it cool down, but that was because of the crappy electric fans the PO installed. Ripped those out and put in a normal Toyota fan clutch and it runs like a top

 

Yep mechanical fans are the way to go, any horsepower you saved with electric fans is meaningless anyway. Even the higher cfm electric fans can't keep up with a mechanical engine driven fan.