G11 and G48 interchangeable?

FCD

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One thing that has me wondering lately, i am looking at possibly buying a 1991 Ford Escort RS 2000 ( European 150hp version )
Looking at fluid recommendations for it i noticed :
The recommended coolant is Ford ESD-M97B4-A

A quick search shows most of the coolants meeting this spec are Blue and claim to meet either VW G11 or G48, or both at the same time.

However, G11 is supposed to be a plain IAT containing Silicate, Borate, Benzoate and some form of Azole.

G48 on the other hand is a Silicate HOAT with no borate ( or benzoate? )

I am confused about how these coolants can be considered interchangeable or meet both specs at the same time?
 
I don't know the specs but decide on one then do a complete flush if worried about the compatibility .
 
Sodium benzoate is an organic acid, and also found in G-05. G-05 uses borate as well to protect cylinder liners, while azole is there to protect copper.

G-11 is VW's old school coolant before G-12(G-30) was used. G-48 is 2-EHA.

In theory, all OATs should play nice with each other but not always.
 
Originally Posted by nthach
Sodium benzoate is an organic acid, and also found in G-05. G-05 uses borate as well to protect cylinder liners, while azole is there to protect copper.

G-11 is VW's old school coolant before G-12(G-30) was used. G-48 is 2-EHA.

In theory, all OATs should play nice with each other but not always.


Borate used to protect cylinder liners? you sure about that?
The only use of Borate in a coolant that i know of is that it acts as a pH buffer, it doesn't have any corrosion inhibitor properties that i know of, in fact it's well known to be aggressive towards aluminium.

Also about 2-Eha being present in G48, i do know of one particular G48 coolant made by a brand called AD that doesn't have any mention of 2-Eha , at least in the SDS, other brands like Glysantin do seem to mention it in the SDS.

So what i understand is that G11 uses Sodium Benzoate as the OAT inhibitor and G48 uses 2-Eha and / or something else depending on brand?
 
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You might be right about borate being a pH buffer - and the reason why the Japanese frown upon borate for pitting. I thought it was a component used in HD coolants to help protect wet-sleeve cylinder liners like what's found on bigger diesels.

The labels on BMW coolant in the US state 2-EHA. As long as the coolant itself or the add pack is coming from BASF it will have 2-EHA. In the US, BASF doesn't sell the Glysantin brand, Valvoline sells all the G-xx stuff under the Zerex label.
 
A formulator/distributor can leave any non-hazardous or trade secret ingredients out of the SDS. 2-EHA is a hazardous chemical but in the concentrations used it can be left out of an SDS or listed as a trade secret, with the option of listing it as a NJRTK disclaimer.
 
Originally Posted by FordCapriDriver
The recommended coolant is Ford ESD-M97B4-A

Isn't it M97B44-A
 
Originally Posted by Schuttwegraeumer
G11 is the VW Product with TL 774 C
G48 is the Glysantin Product with TL 774 C
I dont know if VW used Glysantin these days but this 2 product could be the same.


They do and always have at least in the European produced vehicles use BASF Glysantin.
 
Well right now i am running Repsol brand G11 in both my cars, Repsol customer service was really helpful and confirmed it has Silicate, Benzoate, Borate and Tolytriazole and no 2-Eha.
 
Originally Posted by FordCapriDriver
Well right now i am running Repsol brand G11 in both my cars, Repsol customer service was really helpful and confirmed it has Silicate, Benzoate, Borate and Tolytriazole and no 2-Eha.

So for all intents and purposes this blend of G11 is nitrate free-G05. Probably the closest stuff to the original G11.
 
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Yes G-05 is pretty close but has about Half the Silicate, about 200-300ppm depending on the brand, G11 has 500-600ppm.
I'm not sure what you mean by the closest stuff to the original G11, on the TDS it clearly states that it meets the VW TL-774-C spec which is the original G11, Silicate, Benzoate, Borate and an Azole, and it's Blue which is the colour G11 has always been.
G11 never has had Nitrite ( you said Nitrate but i assume that was a typo , as G-05 has Nitrite not Nitrate ).
 
Originally Posted by FordCapriDriver
Yes G-05 is pretty close but has about Half the Silicate, about 200-300ppm depending on the brand, G11 has 500-600ppm.
I'm not sure what you mean by the closest stuff to the original G11, on the TDS it clearly states that it meets the VW TL-774-C spec which is the original G11, Silicate, Benzoate, Borate and an Azole, and it's Blue which is the colour G11 has always been.
G11 never has had Nitrite ( you said Nitrate but i assume that was a typo , as G-05 has Nitrite not Nitrate ).

Yes nitrite.

Coolants using sodium benzoate are also called HOATs. G05 for example is reddened to as a hybrid by Glysantin themselves. That's where the confusion starts
 
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