Why Do We Need HOAT G05 Coolant?

[220629]

A recent comment got me thinking.

I use the universal antifreeze in my vans, as per my mechanic.

I had an auxillary heater put in the back of my 2005. I left a 1/2 nipple tray in the back of my van, with instructions to use my parts or use heater hose nipples. They did not use metal nipples, used plastic nipples. Plastic nipples were not a good choice, one of them broke, and spewed antifreeze on the hiway. There cheapness cost me an engine, a transmission, and a radiator. I will never use Peterson Dodge in Nampa again.

First. I agree with avoiding the aftermarket plastic hose fittings. There have been more than a few reports of failure. That said, when in an emergency situation national parts stores don't always have brass fittings, only plastic.

Back to topic.

An overview.




http://www.baldwinfilter.com/literature/english/10 TSB's/05-2R1.pdf

Note that per both of my provided references mixing coolants is not recommended, but should not harm your engine.


I found this article very informative.
(I'm partial to most of the stuff that Chevron publishes. It generally includes practical application information, not just warnings and scare tactics.)

Engine Coolant Basics
Paul Fritz, Chevron

https://www.machinerylubrication.com/Read/841/coolant-fundamentals

My comments are based upon the above references.

My reasons to use G05 HOAT Coolant.

G05 is recommended by the manufacturer.
G05 has an extended service interval vs other coolants.
G05 HOAT coolant is designed to coat specific metal surfaces, not the entire system.
G05 HOAT coolant contains anti-cavitation additives.
G05 HOAT coolant will maintain a proper pH for a longer time.

My reasons to avoid other coolant types.

They are not recommended by the manufacturer.
Most have a shorter service interval.
Many have anti-corrosion additives which coat the entire system causing build up over time.
Many do not contain anti-cavitation additives.

Reviewing the provided references will give more detail.

vic


Some information.

From a Database thread.

T1N Engine Coolant

The 2004 Owner Manual specifically mentions Zerex G05 coolant. (Refer above to Post #1.)

The 2006 specifies some other choices.



Euro Peak Coolant Antifreeze, OLD WORLD INDUSTRIES
Zerex G05
Zerex G48
Glysantin G05, BASF AG
Mopar 05066386AA or equiv.

Old World Industries (Peak) is not a small time operation. They manufacture/blend/package products for many different brand labels. From my research the Peak products are considered a quality choice which is still reasonably priced.

For those recommending dealership products only because Zerex G05 doesn't have a Mercedes label... there it is above in writing from my 2006 manual. Zerex G05 and the other listings are fine per Mother Mercedes.

vic

Added:

A reply to an older post.

G48 is very similar to G-05.
...

My understanding is that the G48 formulation was required to meet Euro standards. I believe it relates to their regs... phosphate free. (Maybe gleaned from previous BeVo information?)

There is no reason to stray from the G05 HOAT formulation if you are in N. America.
It appears that Zerex G05 has fallen off the list for MB325.0 coolant. Not because it isn't approved at all, but because it is no longer approved for Euro markets. It has been listed in Owner/Operator Manuals so it remains approved. MB states that the Operator Manual always applies (evergreen).

Added:
"The G-30 is basically the same as DexCool.

The G-05 has more reserve alkalinity than the G-48 and has replaced G-48 as factory fill for Mercedes. [I believe G48 has replaced G05. - vic] They both originate with BASF in Germany in the Glysantin line:

http://www.basf.de/en/produkte/chemikalien/spezial/glysantin/productrange/?id=G0qgQ5i2wbsf1i6

The G-48 is nitrite-free, which means unlike G-05 it can�t be used with wet sleeves. G-05 has a smidgeon more silicate than G-48.

And its [G48] availability in North America is thin, indeed. Valvoline suggests using G-05 to replace it."
https://www.bobistheoilguy.com/forums/ubbthreads.php?ubb=showflat&Number=613531

Zerex G05 has properties which G48 does not.
Nitrites = protect against cavitation.
More reserve alkalinity = longer coolant service life.
Also. (Not G05 specific.)
Carboxylates = cavitation protection.
https://www.machinerylubrication.com/Read/841/coolant-fundamentals

Use G-05 in your T1N. Your head gasket will thank you. Replace every 5 years or 100k. Which ever comes first. Nothing lasts forever.

Also, running your van diluted by DI/distilled water isn't the best idea. Running it for 3 seconds won't do anything. Run it for 5 minutes and you may find that your water pump has started to weep a bit and then full on leak. Water is a decent lubricant but coolant DOES add proper lubrication for the water pump. I used to do the distilled water flush ~10 years ago in Saabs cuz I thought it was brilliant. It's not.

My mode is to change the coolant on the proper schedule. Coolant changed on proper schedule is perfectly serviceable product. It is toxic waste to the EPA, but not to your engine. I won't use any flush chemicals or procedures unless visual inspection or symptoms show the need.

vic

I found the article which I linked above very informative.
(I'm partial to most of the stuff that Chevron publishes. It generally includes practical application information, not just warnings and scare tactics.)

Engine Coolant Basics
Paul Fritz, Chevron

https://www.machinerylubrication.com/Read/841/coolant-fundamentals

 

[fixspr]

A recent comment got me thinking.
My reasons to avoid other coolant types.
They are not recommended by the manufacturer.
Most have a shorter service interval.
Many have anti-corrosion additives which coat the entire system causing build up over time.
Many do not contain anti-cavitation additives.

Recently found some pitting / cavitation damage on my mating surface for EGR had to resurface the Intake side because it was leaking at the coolant passageway, Fluid I suspect was g48 it was a mostly bluish slightest bit green color, I got some G05 to replace it with.

 

[Kajtek1]

I found MB coolants superior in several ways.
Put it in my Ford Trucks, who were used for heavy hauling, therefore having huge fan running quite often.
When with MB coolant the fan stop coming up unless on long and steep grade.
When I could not measure it, lowering the fun run had to bring fuel savings.
When it comes to zerex, each time there is a topic on MB sedan forum about engine overheating, it comes up that the car operates on Zerex.

 

[Nautamaran]

Fluid I suspect was g48 it was a mostly bluish slightest bit green color

Any idea of the coolant’s age? Cavitation is unlikely at the EGR valve, so I would suspect you are seeing corrosion damage. The coolant will keep carrying heat, but pH buffers and anti-corrosion additives are consumables. Once they’re gone the aluminum parts can corrode, creating visible pits as well as an insulating layer of scale that reduces the rate of heat flow to/from the coolant.

-dave

 

[fixspr]

Any idea of the coolant’s age? Cavitation is unlikely at the EGR valve, so I would suspect you are seeing corrosion damage. The coolant will keep carrying heat, but pH buffers and anti-corrosion additives are consumables. Once they’re gone the aluminum parts can corrode, creating visible pits as well as an insulating layer of scale that reduces the rate of heat flow to/from the coolant.

-dave

No Idea on age of coolant, got the Van about a month ago. It was approximately a quarter of a dime size cavity with about 4 or 5 pinholes adjacent to the Pac man Ghost shaped coolant passageway. the cavity was directly adjacent to the passenger top bolt hole.
The visible pits were fairly deep(i'd guess 1-1.8mm), I used a needle to clean them out and brake cleaner waited a day for the chem to evaporate before resurfacing with JB weld a size 8 paintbrush and a razor blade.

 

[Nautamaran]

I would wager the coolant was ancient…

Coolant and brake fluid sit pretty high on the list of under-maintained fluids. (Power steering fluid or rear diff. probably tops the list?)
If it’s full people don’t think of changing it out… five years goes by pretty quickly; the two year flush interval for brake fluid seems ludicrous until you see the dark brown tint of the old stuff exiting the calliper, or worse: see a gush of rusty goo and realize it’s been far too long…

-dave

 

[Kajtek1]

Starting about 2005 MB start adding chem packs to coolant system, what extends coolant life up to 15 years, or 100k miles. It come in different years for different models, so
Check your manual.