Blue Honda Coolant/Blue BMW Coolant - Compatible?

[glennc]

I have another thread going elsewhere about fluids for our new (used) Honda CR-V, but will post this coolant-specific question here. I'm not really up to speed on coolant chemistry/compatibility issues.

Folks on the Honda boards make a big deal about the blue coolant. "Must use blue." Is there any color standardization in the industry that would suggest that these fluids are compatible? Anybody know if they are?

I'd just use the real Honda stuff, but it bugs me that it only comes as premix, so for your $20 with tax you get two quarts of coolant and two quarts of water. I thought BMW coolant was expensive (but tolerable) at $20 for pure coolant.

 

[Fester]

Honda fluid is borate and silicate free.
Contains Water 7732-18-5, Ethylene glycol 107-21-1, Diethelene glycol 111-46-6, lists nothing else.

AA prediluted antifreeze, and Prestone, uses the same exact stuff listed above but add, sodium 2-ethyl hexonate 19766-89-3, and sodium neodecanate 31548-27-3.

Ib have a gallon of each in front of me, for my Toyota truck research lead me to AA coolant when compared to the chemicals in Toyota type antifreeze, with the Honda I played it safe, and got a gallon for $14 at the dealer.

 

[glennc]

Thanks for the reply. That brings up another question. Silicate free I sort of understand, silicates are hard particles that scrub the internals. BMW coolant says it is nitrite and phosphate free, "greatly reducing the possibility of harmful deposit formation," which I believe but do not understand. Now you mention "borate free."

What do the latter three mean, in a chemical and functional sense, and how would one find out whether a various aftermarket brand is free of the things a particular automaker wants it to be free of?

 

[glennc]

Zerex' website shows their Dex-Cool-compatible coolant as the best choice for Hondas of this year. I have a bottle of Havoline long life Dex-Cool anti-freeze in the garage that says it is silicate, phosphate, nitrite and borate free. It seems this would be a good choice, but... one poster in another thread said he uses G-05 in his CR-V, would that be better? And I gather that there are lots of problems with Dex-Cool in general, but have not learned what sorts of problems these are or what causes them.

I'm sufficiently ticked of at Honda's way of selling coolant to go aftermarket if it won't compromise protection.

 

[Craig in Canada]

BMW blue coolant is Zerex G-48, as far as I know. Many BMW owners use G-05 with success, but G-48 is not the same. Volvo blue is also G-48, I believe. No idea about Honda.

My recollection from another reference thread:

- G-48 has better compatibility with some plastics, in particular plastic water pump impellers

- G-05 is nitrited, G-48 is nitrite-free

- G-05 has more silicate

- both are HOAT, non-phosphate, low-silicate, low-pH



This thread was the source of some of the info but is broken at the moment:

http://www.bimmer.info/forum/showpost.php?p=233833&postcount=20

 

[durango7]

Here's an interesting document I found on a online Honda dealer's parts website: H and A Honda - Coolant Sevice Bulletin from May 1995

Also, some information about Honda Coolant concentrate in 1 liter bottles.

Bernardi Parts - Accord Block Heater instructions with Coolant Concentrate

Honda Accord Service Bulletin - increasing coolant concentration to 60%

 

[glennc]

Originally Posted By: Craig in Canada
BMW blue coolant is Zerex G-48, as far as I know. Many BMW owners use G-05 with success, but G-48 is not the same. Volvo blue is also G-48, I believe. No idea about Honda.

My recollection from another reference thread:

- G-48 has better compatibility with some plastics, in particular plastic water pump impellers

- G-05 is nitrited, G-48 is nitrite-free

- G-05 has more silicate

- both are HOAT, non-phosphate, low-silicate, low-pH



This thread was the source of some of the info but is broken at the moment:

http://www.bimmer.info/forum/showpost.php?p=233833&postcount=20

Great stuff. But... if G-48 is "low-silicate," and BMW coolant claims to be "free of" silicates, then how can BMW coolant be G-48?

Among the commercially available Zerex mixes you have standard green, G-05 and Dex-Cool. The latter is the only one that claims to be silicate-free, right? Wouldn't that be the only good choice for a Honda, with notorious incompatibility with silicates? But again, I keep hearing of all these "problems" with Dex-Cool. What are they? Will I have them?

I am leaning towards the Havoline Dex-Cool silicate, nitrite, borate, phosphate free stuff, which is orange IIRC. Good choice?

 

[FowVay]

Glenn, BMW doesn't claim that their coolant is free of silicates. I have a gallon of their coolant sitting in front of me. Here is what is written on the gallon container:

"This ethylene glycol based antifreeze contains no nitrites or phosphates, greatly reducing the possiblity of harmful deposit formation."

The ingredients list is as follows:

Ethylene glycol (107-21-1)
Diethylene glycol (111-46-6)
Sebacic acid (111-20-6)
Sodium hydroxide (1310-73-2)
2-Ethylhexanoic acid (149-57-5)
Corrosion inhibitors, Defoamers, Silicates, and Dyes.

This coolant is in fact Glysantin G-48. The similar product to Dex-Cool would be the pink coolant from VW/Audi which is Glysantin G-30.

If I had a Honda of any model I'd use Zerex G-05. It's readily available, a incredibly good chemistry that's been proven for decades, and it's priced correctly although more expensive than the generic Prestone's. Zerex G-05 is a 4 year coolant, BMW's G-48 is a 4 year coolant, VW's G-30 (actually called G-12+ at VW) is a lifetime coolant.

 

[Craig in Canada]

What FowVay said.

I believe I've only ever seen "low silicate" claims from BMW and both G-05 and G-48 are "low", but G-48 is lower.

You may also want to look through page 2 of this link:

http://www.englefieldoil.com/PDF/Zerex_chart.pdf

It indicates that OEM fill for BMW is G-48, and suggest G-05 as a readily available aftermarket sub. It also indicates G-05 for Honda.

 

[glennc]

Originally Posted By: FowVay
Glenn, BMW doesn't claim that their coolant is free of silicates. I have a gallon of their coolant sitting in front of me. Here is what is written on the gallon container:

"This ethylene glycol based antifreeze contains no nitrites or phosphates, greatly reducing the possiblity of harmful deposit formation."

You are indeed correct as I have the same bottle in front of me and it agrees with yours. Apparently a case of siliconfusion.

So... my current understanding including some of the useful information from this thread:

- Honda coolant is silicate free and BMW coolant is not: they are obviously not related.

- G-48 is low silicate and is the same as the BMW coolant and consequently is not the same as the Honda coolant.

- Honda specifically requires a coolant that is free of silicates. Its coolant is also borate free.

- G-05 is not silicate free and in fact has more silicates than G-48.

- The coolant manufacturers recommend their Dex-Cool coolants for use in my CR-V.

That leaves me with a few questions.

- Would it not be best to rule out G-05 and G-48 based on the silicate issue if nothing else?

- What is it that people do not like about the Dex-Cool chemistries?

- Would there be any disadvantage whatsoever to using the Dex-Cool products in place of the Honda coolant?

- Is there anything I'm missing? Apparently the chemistries are more complicated than just silicates and borates.

Finally,
Originally Posted By: FowVay

If I had a Honda of any model I'd use Zerex G-05. It's readily available, a incredibly good chemistry that's been proven for decades, and it's priced correctly although more expensive than the generic Prestone's.

The silicates wouldn't turn you off? Maybe there is more to this than I'm getting...?

 

[FowVay]

I am only stating that based on my personal experiences I would use one of the Glysantin coolants, either G-05, G-48, or G-30. G-05 was developed for heavy-duty truck applications that used cast iron engine blocks, aluminum cylinder heads and copper cooling system components. It works amazingly well with these hybrid systems.

G-48 is a milder version and worked well until the HOAT coolants came on the market in the middle 1990's. Most European companies moved from OAT silicated coolants in favor of the longer lasting HOAT silicate free coolants in a effort to reduce the maintenance requirements. To my knowledge there was no durability issues with the OAT coolants and personal experience has shown 10 year old systems that were fed a steady diet of G-48 in spotless condition.

There is nothing special about a Honda cooling system. However, Honda knows that the HOAT coolants will last longer and they have tested and approved the use of their coolant so they endorse it. If the system were to never be opened and they promoted a 'lifetime' fluid then I'd definitely use either the Honda coolant or a compatible HOAT such as the VW G-12+. However, most cooling systems get opened when the water pump is changed during a timing belt service so that generally puts a service life of 5 years or less on a coolant.

I personally prefer the Glysantin coolants because they are head and shoulders above products such as the green Prestone, Peak, standard Zerex, etc.

I do know that Glysantin does make a different 'Dex-Cool' formulation for General Motors so it is not the same as the other HOAT coolants. My only experience with Havoline Dex-cool was in a application where it was not specified. I put Dex-Cool in a Ford Escort back when Dex-Cool first went on the market. Within a few months the gasket at the thermostat housing deterioted and started leaking. I have seen numerous GM cars with sludged coolant reservoirs and clogged radiators that used Dex-Cool but I honestly can't say that it was the fault of the coolant. I personally believe that the fault is with the poorly designed manifold gaskets. All Dex-Cool failures that I have seen were on V-6 equipped GM cars. I didn't bother to investigate further so I can't say the problem was with the coolant.

 

[glennc]

That makes perfect sense, of course. I have always assumed that you should stay with the oem's chemistry, believing that there might be incompatibilities between the coolant chemistry and the materials the coolant will contact in use. For example, I know Honda has had problems with silicates in both motorcycles and cars, even though those coolants will work fine in other vehicles indefinitely. BMWs, I understand, are prone to have heavily eroded cylinder head coolant passages, and head gasket problems, if used with standard "green" coolant. Some systems presumably require silicates to help mechanically clean the system's internals; and BMWs, I have recently learned, are designed to have coolants that contain phosphates, which I have heard coat the system's surfaces to help protect them.

So I had sort of concluded that unless you knew the chemistry of a coolant in detail and how it would interact with all the materials used in your particular system (way over my head, obviously), the only safe bet was to stay with a coolant that at least used the same chemistry as the OEM coolant.

If Dex-Cool is OAT and Honda uses an HOAT chemistry, would that mean that the Dex-Cool, even though it is free of the silicates and phosphates and so on, is not really right for the Honda?

I checked again, Zerex says to use their Dex-Cool product, but Havoline does not. They recommend their regular non-long-life green stuff. Makes me wonder why, and I suspect that there are important details of the respective chemistries that I still don't know about.

It makes me want to throw up my hands again, as I did before with the BMW stuff, and just go with Honda. I have always believed that if you use the right coolant, most systems will last pretty much forever with no degradation at all, and that is my goal. But I still don't want to pay my Honda dealer $40 for a gallon of coolant and a gallon of water.

 

[Carmudgeon]

Color is no judge of coolant chemistry, and a poor way to determine compatibility.

BMW and older pre-Dexcool Saabs use blue G-48, while Volvo uses green.

OTC Zerex G-05 is a very pale yellow, while I'm sure the Ford and Chrysler OE versions are dyed in their own colors.

I recall an article in a trade rag discussing colors, coolant chemistry and the various philosophies about why each type is specced. Engine composition is one factor, but differences in local water quality also play a large role.

G-05 contains more silicate than G-48, but they're both considered low-silicate, and very similar overall. The datasheets from Zerex and BASF detail the differences.

 

[glennc]

Looks like it's all moot, I have thrown in the proverbial water pump and decided to go with the Honda coolant. Having found a source at $12/gallon (premix) I can live with the cost, barely, and although I'm probably being overly conservative, not having absolute knowledge as to whether an alternative would do actual harm is enough to make that palatable.

Thanks for all the commentary, I have certainly learned a good bit.

 

[gaspo]

I think you’ve never set your foot in Honda dealership parts store before. $12/gallon pricing was for ages and $9... online but even at $20 wouldn’t be overkill knowing you doing right thing and coolant can last up to five years. Sure, some all makes and models concentrate brew at $5 two gallons on sale feels better..

 

[glennc]

Gaspo, I've been buying parts from Honda dealers since 1988, off and on, as I've owned Hondas. However, I do not agree with a complacent approach to high dealer pricing and will always look for reasonable alternatives when they are available.

 

[FowVay]

Glenn, I would do the same thing as you suggest and just go to the dealership and get a gallon or two. Coolant is not something that you replace with every tank of fuel so the cost is not that prohibitive.

I know I'm crazy but if my car came with red coolant in the reservoir then I'd like to keep it that way. I tinker around on VW cars for a hobby and it kills me to see a A4 or B5 chassis car come in with green anti-freeze.

 

[BuickGN]

I played it safe and went with the Honda stuff. Just be careful, both gallons I bought at separate times were not only pre-mixed, they were "pre-used" by the dealer.

 

[CARMandP]

Nice. Preused?

How about the Amsoil Antifreeze? Can anyone tell me how well their product will work?