Ethylene Glycol: To OAT or non-OAT?

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Hello all,

I have a bit of a backstory so I will put the tldr short version here:
If OEM calls for an OAT (Organic Acid Technology) Ethylene Glycol coolant, and I use a plain Ethylene Glycol one, will I cause problems with the engine/radiator?


Kinda long backstory:

I recently bought a 2012 Suzuki Swift with the 1.2L engine.

It looked like it had the original Suzuki OEM coolant, it's a particular green colour which is what they use in the factory.

It has good service history but the last few stamps are from independent garages so I decided to assume the coolant had never been changed and do the fullest and most complete service possible (the car isn't for myself, but for a family member). I have replaced every filter and fluid in the car plus the brake discs and pads - and had an alignment done.

I had planned to use all genuine parts but the local Suzuki dealer told me that the green OEM coolant was no longer in production, but they could sell me a red variety which would require a complete flush as it shouldn't be mixed with the green. I was fine with this but then they also told me they couldn't sell me a 5L container of oil because they buy it in bulk. They recommended I buy non-genuine oil from an independent shop. Because of this, I decided to get everything from a more convenient and reputable parts chain here in the UK, where I normally buy all my filters and fluids for my Toyotas. I would be able to get all the filters, fluids and brake parts from one place so it was more convenient and probably cheaper.

At this shop, I gave them my make and model and got all the filters, fluids and brake parts. They have an in-house brand that has become very popular in independent garages and meets a lot of Ford, VW requirements and ACEA specifications for oil and coolant. They also have Shell, Castrol, Petronas oils. Bosch, Mann, and Fram filters etc. so they are trusted in that sense. Their in-house brand of coolant seems to cover every modern car requirement, they have 3 varieties:

Blue - Ethylene Glycol

Pink - Ethylene Glycol with organic acid technology (this is what goes in my Toyotas as the OEM is also an OAT Ethylene Glycol and happens to be pink/red) (I think this is what is known as the controversial Dexcool in the USA? Not sure if any GM Europe stuff uses it)

Purple - HOAT (hybrid organic acid technology) (not sure if its ethylene glycol but contains silicates? Seems to be for newer VW Audi stuff as it carries the G13 label)

They said I needed the blue one for the Swift.

So I drained and flushed the hoses and radiator with a garden hose, filled with distilled water, went for a drive and repeated a few times till there was no trace of the green stuff in the drained water. I mixed the blue coolant with 50% distilled water and filled it up and called it done.

Now a few weeks later, I'm looking back, I can't find the specs for what the green Suzuki coolant was or who makes it. Ideally, I wanted that green OEM stuff so I could just drain the radiator and fill it back up, the car is fairly new and low miles so it didn't need a full flush, only I didn't want to mix different coolants so I flushed it all out.

I emailed Suzuki customer service and asked for more information and they told me to use Ecstar Long Life Coolant. Frankly, I've never heard of this and I can't find any information on the specification of this coolant and whether its OAT or not but if it's red/pink I'm assuming its OAT.

The owner's manual for the car just says ethylene glycol, there is no mention of OAT but I think this is just an omission for the sake of simplicity as my Toyota one doesn't mention OAT either.

So, should I flush it out and refill with the OAT stuff what? If Suzuki has switched to OAT because they don't make the green stuff anymore, then I'm happy to continue using the non-OAT one but I'm not sure. if it came with non-OAT from the factory, then is there any sense in changing? The main problem is the lack of information, which is something I wasn't prepared for with my Toyota background.

Thanks for reading, apologies for the long story. There seems to be a mis-match in terminology used across USA/Europe, I don't see any American brands classifying their coolants as OAT and non-OAT but that could be my ignorance. Any advice/opinion is appreciated - thanks.
 
I've always thought ethylene glycol was OAT. My Liberty takes HOAT and I know for a fact that OAT coolants are totally wrong for it. My XJ takes anything ethylene glycol which would mean not HOAT so that must be OAT.

I use the green Prestone OAT stuff for my XJ, so I'm guessing that you'd be good with that. You don't want to mix OAT and HOAT but I think running HOAT in something that was originally OAT is ok but not the opposite.
 
Hi Mate,

There are three basic coolant types, the old school IAT (inorganic adds - like silicates and boron etc) this worked well but needed to be changed regularly ( ~ 2 years). It was traditionally green in colour, but this is only a dye, and colour isn't enough to correctly ID a coolant - they can be any colour. No car built in 2012 should come from the factory with this as it's factory fill (FF).

Then you have OAT (organic acid technology) stuff like Dex-Cool, G40, G12 etc. They last a long time ( maybe 6-8 years) but the system needs to be sealed and designed around the coolant, correct polymers, no lead solder etc. No problem for most modern cars, but a few historic problems, not all due to the coolant - sometimes a bad design blamed on the coolant.

Then you have the middle ground, HOAT (hybrid organic acid technology) with uses both OAT and a low dose of IAT. The IAT gives quick coverage to new metal, while the OAT gives a longer coolant life. Typical examples are G05 ( Green) and G48 (BMW coolant - blue). They last about 4 years. There are some regional preferences, European HOAT tends to be phosphate free (for hard water) while Asian coolants tend to be silicate free (for high concentrations water pump issues) - neither is a big deal for a system that is properly maintained like yours with distilled / demineralized water with the correct coolant concentration.

All coolants are based on Ethylene Glycol (EG) or something simiilar like PEG. The EG is the anti-freeze and anti-boil part, while the adds (IAT. OAT, HOAT) are for corrosion control.

All modern systems should work with any coolant, as long as you do a full drain and flush first, so as not to mix coolant type.

You have done a proper flush, so you are fine with whatever you have in there.

Me ? I use the correct coolant if I can easily find it (Dex-Cool in my Opel right now) but if I can't then a drain and full flush, then I just replace with Zerex G05 HOAT and carry on.
 
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HoosierJeeper I'm not sure if that's true, I think there exists OAT and non-OAT Ethylene Glycol based coolants.

I have seen information about the compatibility of OAT and HOAT which agrees with what you say, but at this point, I'm trying to determine whether to use plain Ethylene Glycol or OAT.
 
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Quote:
Blue - Ethylene Glycol

Pink - Ethylene Glycol with organic acid technology (this is what goes in my Toyotas as the OEM is also an OAT Ethylene Glycol and happens to be pink/red) (I think this is what is known as the controversial Dexcool in the USA? Not sure if any GM Europe stuff uses it)

Purple - HOAT (hybrid organic acid technology) (not sure if its ethylene glycol but contains silicates? Seems to be for newer VW Audi stuff as it carries the G13 label)

They said I needed the blue one for the Swift.


Complete guess here, as I need to know chemistry and codes, but I would guess:
Blue - G48 (or G05) HOAT, probably the blue BMW G48 stuff (which is much the same as Audi G11 and close to Jeep / Ford G05).
Pink - G30 or G12 or DexCool OAT
Purple - G40 or G12++ or G13 HOAT (phosphate free )

Given the above guess, the blue G48 / G05 HOAT would have been my pick.
 
Quote:
Then you have OAT (organic acid technology) stuff like Dex-Cool, G30, G12 etc. They last a long time ( maybe 6-8 years)

Typo Fixed: it's G30 that is OAT (not G40)
 
Shame on the industry for picking dyes the way they did. Color means NOTHING and has been nothing but a source of confusion on this topic.
 
Originally Posted By: geetar
HoosierJeeper I'm not sure if that's true, I think there exists OAT and non-OAT Ethylene Glycol based coolants.

Yes. Ethylene glycol has been the "base stock" of almost every coolant on the market for many decades, which is why, when an OEM says to use ethylene glycol antifreeze, it's so frustrating, since that really says nothing. It's akin to a manual recommending you use a motor oil with a phosphorus based anti-wear package, but saying nothing else at all.
 
Thanks for the reply.

I don't think the blue one is HOAT because HOAT is fairly new and they've been selling this exactly blue one for several years and it's the cheapest one with a lifespan of only 2 years. I think HOAT is the more expensive purple one in their line up.
 
Originally Posted By: Garak
Originally Posted By: geetar
HoosierJeeper I'm not sure if that's true, I think there exists OAT and non-OAT Ethylene Glycol based coolants.

Yes. Ethylene glycol has been the "base stock" of almost every coolant on the market for many decades, which is why, when an OEM says to use ethylene glycol antifreeze, it's so frustrating, since that really says nothing. It's akin to a manual recommending you use a motor oil with a phosphorus based anti-wear package, but saying nothing else at all.


This. It's very frustrating especially when the factory one is discontinued, at least I could just get the factory one from the dealer and not have to care about the chemical content (assuming they got it right initially!)

Its quite disappointing because otherwise, the Suzuki owners manual has quite a lot more technical information such as torque specs and a bunch of other stuff that I haven't seen in Toyota ones. It says stuff like change your oil every 4,000 miles if you only do short trips in town and city - which is something I've always said and recommended to people but never seen it in a standard owner's manual.
 
Originally Posted By: geetar
Thanks for the reply.

I don't think the blue one is HOAT because HOAT is fairly new and they've been selling this exactly blue one for several years and it's the cheapest one with a lifespan of only 2 years. I think HOAT is the more expensive purple one in their line up.


Yes, two years sounds like old-school IAT stuff. It works well, it just needs to be changed more regularly. And yes it's often much less expensive.

It will be EG based, like all of them.

Shame it's blue in colour, that is very confusing, as IAT has always been green colour, with blue/red/pink/purple mostly being used with the more modern stuff. Still it's all just dye.

A good flush and filled with 50% IAT, you are good to go for another two years. Drive the car and worry about it then, or just use the same again when the time comes.
 
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As noted here several times, majority AF's are ethylene glycol based, be they IAT, OAT or HOAT. For the topic Suzuki and using Pentofrost/Pentosin AF look up and inforamtion the original spec AF is an Asian PHOAT/phosphated OAT. In Pentofrost and is green tinted A2 concentrate was the older shorter service interval (2years/30k miles) AF. Newer PHOAT are longer service interval, ~5years/50k miles in subsequent d&f service but mostly come as a premix.

PHOATs use no silicates, amines, nitrites or borates. And also no Asian AF recommends or uses 2eha as an inhibitor.

If you go to an 'OAT' I would avoid an AF using 2eha which is a primary inhibitor in DexCool and universal dexclones.

In HOAT, low silicate G05 would likely be an acceptable substitute if no Asian PHOAT available. That would be with complete flush/exchange.

No being familiar with AF availability in England, you'll have to do research on which AF available there will fill the bill given the information provided above. I'd add don't try and go by AF tint/color alone when picking a suitable AF as color is very unreliable in determining chemistry or AF type.
 
BTW I went coolant shopping today, needed some top-up fluid and I wanted it to be exactly the same as what is in there already. Zerex Dex-Cool from Valvoline.

I had to go to three different shops before I found exactly what I wanted. Even though every autostore I went into had a wall of coolants in all the colours of the rainbow.

Coolant shopping is very confusing.
 
Originally Posted By: Sayjac
For the topic Suziki ... the original spec AF is an Asian PHOAT/phosphated OAT. In Pentofrost it is green tinted A2 concentrate which was the older shorter service interval (2years/30k miles) AF. Newer PHOAT are longer service interval, ~5years/50k miles.

PHOATs use no silicates, amines, nitrites or borates. And also no Asian AF recommends or uses 2eha as an inhibitor.

In HOAT, low silicate G05 would likely be an acceptable substitute if no Asian PHOAT available.

Thanks Sayjac, nice work.

So it is a HOAT but in the flavour of a PHOAT, which makes sense to me.

Never being able to find that in Australia, I used G05 in all my Japanese motorcycles without any problems.
 
Thanks for all the replies.

I think coolant shopping is definitely difficult, more difficult than oil shopping at least. And because coolant tends to stay in there for a few years, I feel like it's important to avoid getting it wrong.

The colours are a nightmare but I wasn't relying on that as a form of identification, but I did know that the OEM Suzuki one is a green colour because I looked at several models at the dealership. Green coolant is very uncommon in the UK, they're mostly red or pink which is annoying because it just looks like rust water in the radiator.

One of the other cars in the family is a 2015 3-cyl turbo Renault, this one has a green coolant and due to be replaced. Luckily I can get this from the dealer and just drain the rad and refill. The only rough part is the garage procedure to do it requires removing the front bumper! There are no drain plugs on the block or radiator and the bottom hose is inaccessible with just the undertray removed.

Sadly we don't have Pentofrost in the UK. But a good British company is Comma, when I put the Suzuki Swift into their website, it returns the same OAT coolant that it thinks should go in my Toyota. It has the following information in the tech sheet:

Glysantin® G30® by BASF is approved by: Audi/Bentley/Bugatti/Lamborghini/Seat/Skoda/VW (TL774-D/F); DAF (MAT74002); Deutz (DQC CB-14); Jaguar vehicles built from 1999 (VIN 878389); MAN (MAN 324 SNF); Mercedes Benz (MB-Approval 325.3); Mini Cooper D from 2007-2010; MTU (MTL 5048); Porsche vehicles built between 1996 and 2009; Siemens (wind power).

Because of this, I think OAT would've been the better choice but now that it's all flushed and done and based on your advice, I think it should be OK to stay with the non-OAT coolant in the Suzuki, and just replace it every 2 years.
I don't mind the extra maintenance, Suzuki has put a drain plug in the bottom of the rad so it's quite easy to just drain and refill during an oil change or something.
 
Yes, it can be very confusing.. In the U.S. G-05 can be pink, orange or pale yellow. Must read the label. G-48 is used in the later Chrysler products and is purple.. I have had good experience with both. Having said that, I have several old cars that have Wal-Mart brand All makes-all models, (AMAM) in them, which is basically Dex-cool. These cars are currently in storage, waiting for a rebirth.
smile.gif
I am switching each to G-05 as I make them roadworthy. In my mind, G-05 is close to a universal coolant. Rated for 5 years or 50,000 miles. I personally recommend it.

Good luck,

Wayne
 
Originally Posted By: SR5
Quote:
Then you have OAT (organic acid technology) stuff like Dex-Cool, G30, G12 etc. They last a long time ( maybe 6-8 years)

Typo Fixed: it's G30 that is OAT (not G40)


The BASF/Glysantin Spectrum:

http://www.mas-ft.de/kuehlmittel/
https://translate.google.com/translate?sl=de&tl=en&js=y&prev=_t&hl=de&ie=UTF-8&u=http%3A%2F%2Fwww.mas-ft.de%2Fkuehlmittel%2F&edit-text=&act=url

The new G64 Glysantin is not in the list, its a PSiOAT, at the moment only for Volvos.
 
So it looks like in the Glysantin line, G30 would be an acceptable Long Life OAT for the OP's Suzuki. Using an Amazon UK description of the Comma brand HERE looks similar to a Asian PHOAT here. Difference being no P/phosphate in G30. I've read that because of hard water, Euros eschew use of P in AF. Only thing I can't tell is if G30 uses 2eha an inhibitor, same as DexCool OAT? Personally I'd want to know that.

Here in the States, I'm using a Long Life OAT with no P and no 2eha as a replacement for a PHOAT in a Tacoma. It's Peak Global Lifetime. Similar characteristics to no silicate G30. Using it now ~4 years, with original radiator. Many like G05 as 'universal' type AF. Because of personal use, I'd have to give Peak Global Lifetime the nod there.
 
Glysantin says:

http://www.glysantin.de/fileadmin/Files/...W_EN_170522.pdf

BASF is a european company.
I do not know how available these products are in the USA.
ebay?
Amazon?

The typical US products like PEAK or Havoline are not whide spread in the EU.

EDIT: The OP is from GB.
Glysantin G30 is VW G11 or VW TL 774 F (VW norm for VW, Audi and Skoda)
This coolant should be good available in the whole EU.
 
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