Why So Many Different Coolants?

[joesregalproject]

Okay folks. Today I did a coolant flush and fill on my F150. It's a 2015, came with Motorcraft orange, basically a Dex-Cool clone, coolant from the factory. Ford has now discontinued that coolant in favor of a "yellow" Mountain Dew colored, P-OAT coolant that replaces and supercedes the old orange. It is supposed to be a better coolant and somehow completely compatible (but not really?). Now I can remember from when I was at the dealer that Ford had 4 different coolants for different vehicles- green, gold, dark green, and orange. Now this makes 5. Asian makes use their own coolants. European makes use their own coolants. GM has stuck to Dex-Cool for pretty long, so I gotta give them props. Mopar has an OAT and a HOAT, one purple and one orange.

But why are there so many different types and colors of coolant and why has this not become color-coded and standardized yet? At minimum, there are IAT, OAT, HOAT, P-HOAT, and P-OAT coolants. I'm not enough of a chemist to understand what all that means, but I know that I don't want to star5 practicing chemistry experiments in my cooling system.

And if there are all of these specialized application-specific coolants, what the hell is Prestone All-Vehicles Coolant that claims to be compatible with everything?

Just to illustrate this ridiculousness, I went and found a few coolant compatability charts online. Zerex even contradicts themselves.

 

[pagrunt]

What, not big truck companies or engine manufacurers on those list? We have 3 different types just for the International trucks alone. Then different types for the Macks depending on engine, the lone Western Star tractor & the few Damlier Sterlings. I'm not getting into the tractors & other equiptment. I swear the state spends as much on coolant as they do on fuel.

 

[86LK]

I'm not a chemist but that's basically who you'll need to get a proper explanation of why certain mixtures. Strictly speaking, all coolants will work in all vehicles but use of the wrong one will cause problems due to metallurgy and chemistry. Some of them will shorten the life of your engine.
All I know is it sucks to have to stock them all when truck comes in on Wednesday night to the store.

Peak Asian: Red/Pink, Green, Blue
Peak Euro: Blue, Violet, Pink
Peak North American: Gold, Orange
Peak Normal: the green schtuff
Peak Dexcool: the orange stuff
Peak Fleet: SCA, Final Charge

and you have to read carefully because some of the manufacturers flip-flopped from one color to the next at some point. thank gd the label on the front clearly shows that!

......and then we have to stock all the equivalent Prestone crap

 

[69hurstolds]

For those who care-

IAT is Inorganic Acid Technology. OAT is Organic Acid Technology. HOAT is Hybrid Organic Acid Technology. (P- prefix for phosphate enhanced)

IAT is your conventional stuff. It's typically good for 2 years and 30K miles. The HOAT is a bit better at 3 years and 60K miles. Depends on the manufacturer and additive packages.

The OAT is supposedly all non-hazardous, so that's a good thing. Light duty is typically 5 years and 150K miles, but in the heavy duty versions for the big trucks, etc., it's supposed to last up to a million miles. AKA, lifetime coolant.

YMMV.

 

[69hurstolds]

I use Motorcraft stuff in the 2012 Focus. A couple of years ago, I replaced all the hoses/belts etc., and the coolant changed from the original orange to the "new" yellow. So now it has the yellow in it. It's supposed to be good for 10 years/200K miles until the first change, then 5 years/(can't remember mileage but it won't matter now), after that.

 

[joesregalproject]

I'm not a chemist but that's basically who you'll need to get a proper explanation of why certain mixtures. Strictly speaking, all coolants will work in all vehicles but use of the wrong one will cause problems due to metallurgy and chemistry. Some of them will shorten the life of your engine.

You really do need to have some sort of chemistry degree to figure it all out. I play it safe and just don't mix anything.

I use Motorcraft stuff in the 2012 Focus. A couple of years ago, I replaced all the hoses/belts etc., and the coolant changed from the original orange to the "new" yellow. So now it has the yellow in it. It's supposed to be good for 10 years/200K miles until the first change, then 5 years/(can't remember mileage but it won't matter now), after that.

I believe the mileage is the same for subsequent changes, but the time is reduced, so 5 year/100k. Now that I've flushed from one to another, I'll probably drain and fill once every couple years. For my truck, the system capacity is 16.4 quarts, but only 8 comes out with a drain.

What I find odd, is that Ford is switching to a phosphated coolant, which manufacturers originally didn't use in North America because supposedly the phosphates react to hard water, which is prevalent in most of the country. I also noticed that Ford didn't really emphasize not using tap water with the new coolant, which makes me wonder if it was formulated to be more compatible with hard water than phosphated coolants of the past. Because while I'm sure most of us here use distilled water with coolant, I know plenty of dealers and shops mix with straight tap water.

 

[69hurstolds]

Yeah, it's weird. I know UK doesn't use phosphates in their coolant.

And yeah, I use concentrate and mix my own 50/50 with distilled.

 

[wskirvin]

What, not big truck companies or engine manufacurers on those list? We have 3 different types just for the International trucks alone. Then different types for the Macks depending on engine, the lone Western Star tractor & the few Damlier Sterlings. I'm not getting into the tractors & other equiptment. I swear the state spends as much on coolant as they do on fuel.

I have seen 4 in Kenworth's over the years

 

[joesregalproject]

Yeah, it's weird. I know UK doesn't use phosphates in their coolant.

And yeah, I use concentrate and mix my own 50/50 with distilled.

It is strange. I usually flush with tap water from the hose and whatever water stays in the block is what it is, but I always refill with concentrate and distilled mix. Our water here is slightly hard but not as bad as everyone thinks it is.

 

[69hurstolds]

That works. If your water is clean, there shouldn't be TOO much issue with residual water. We have well water which is really clean and remarkably is clean as all get out. The only thing that's f-d up about it is it's slightly acidic at around 6.17 pH on the meter. But with the slightly higher pH of the antifreeze, I'm not too worried about it. Last time on the Focus I got a 7.30 final pH after the test drive and cooldown, so I felt ok with it. I send off well samples to the lab every couple of years and the TDS is super low. We have an undersink RO unit for drinking water with a mineral final filter (to raise pH) that boosts the pH to around 7.4 and I'm good with that. I ran a tap off to the ice maker and fridge water so that water is in good shape too.

I'll flush with filtered well-water until it's clear, drain what I can, and add about 1 quart of straight concentrate, followed by my 50-50 mix with distilled water. I check with the antifreeze tester anyway, and top off with the 50-50 as needed. Seems to work ok and I'm good to go here in the south. I'm always in the -20F freeze protection or better, so if it ever gets that cold here, winter can have it.