2-EHA in G48/HT12 and glass reinforced plastic

Joined
Apr 15, 2010
Messages
14,153
Location
Atlanta,GA
I came across a comment which said 2-EHA will over time attack the plastic connectors in BMW cooling systems. I've only been able to find information pertaining to silicone hoses.

Any insight would be appreciated because if true I may consider using a universal coolant in my mother's B58 and perhaps my own N55.
 
I believe BMW has replaced their blue LC-87 coolant with a more modern and more environmentally responsible coolant LC-18 (sold by Valvoline as HT-12). The new coolant is green and to replace the LC-87 product. 2-ethylhexanoic coolants have been phased out in the European Union and are no longer sold in the small "consumer size" liter packaging.

I converted my BMW over to Zerex Asian Blue coolant years ago and have had no issues. I run it in my old E46 BMW, my Nissan Frontier, my Kawasaki ZX-14R and once I use up all of my G-13 VW coolant I will run it in my John Deere lawn mower.
 
I believe BMW has replaced their blue LC-87 coolant with a more modern and more environmentally responsible coolant LC-18 (sold by Valvoline as HT-12). The new coolant is green and to replace the LC-87 product. 2-ethylhexanoic coolants have been phased out in the European Union and are no longer sold in the small "consumer size" liter packaging.

I converted my BMW over to Zerex Asian Blue coolant years ago and have had no issues. I run it in my old E46 BMW, my Nissan Frontier, my Kawasaki ZX-14R and once I use up all of my G-13 VW coolant I will run it in my John Deere lawn mower.
Apparently HT12 also contains some amount of 2-EHA.

Edit: I noticed Gysantin G48 is now advertising as being free of 2-EHA and they're recommending G64 (HT12).
 
Last edited:
Febi Bilstein here in Europe specifically state in the TDS For the new Green BMW 18LC Coolant that it is 2-Eha free.

Screenshot_20241202-183329.webp
 
Interesting about the Euros (at least some) now specifying no 2eha AFs. In that respect, following the vast majority long time OEM Asian AFs.
 
I came across a comment which said 2-EHA will over time attack the plastic connectors in BMW cooling systems. I've only been able to find information pertaining to silicone hoses.

Any insight would be appreciated because if true I may consider using a universal coolant in my mother's B58 and perhaps my own N55.
The silicone thing is left over from the 90’s. Prestone sells Blue “European” coolant containing 2EHA and it replaces both G-48 and G-64. Guaranteed.
 
Prestone using 2eha has been SOP for Prestone AFs, no matter what whether called/labeled "Asian"( phoat) or as here topic Euro AFs. If one is ok with not matching the OEM AFs specifically avoiding 2eha as inhibitor, then Prestone could be an option. I'm not one of those folks.
 
Disclaimer: not a chemist, but was highly interested in chemistry and pretty good at chemistry in college.

I believe that the issue with 2-eha and harming of certain plastics and gasket materials is a valid issue, but it's more of an issue "in a vacuum."

I believe that Prestone uses 2-eha with confidence because they

a) use a lower concentration of it than in earlier, more problematic coolants

b) extensively buffer the coolant to prevent 2-eha from attacking plastics and gasket materials

The main issue of 2-eha attacking nylon 6,6 is valid, yes. The issue with nylon 6,6 is its susceptibility to hydrolysis. The hydrolysis is more favored in acidic environments than in basic environments. Coolant starts off as basic, that's why we have coolant pH test strips and usually we're looking for a value between 8 and 10 when dipping the coolant. An acidic coolant is one that needs to be replaced. I believe that on earlier cars, that used 2-eha, there were issues with air mixing with the coolant, which accelerated the breakdown of the ethylene glycol into acidic byproducts, which created a favorable environment for 2-eha to do its thing to nylon plastics. Something that's emphasized a lot in chemistry is the importance of pH in aqueous chemistry, and how pH can stabilize or destabilize molecules.

It seems reasonable that in a well-sealed cooling system, with minimal amounts of air intrusion, with a coolant that has a robust pH buffering package that keeps the coolant basic, and with a coolant that has a minimal concentration of 2-eha, that 2-eha would have minimal effect on nylon. An acidic pH would increase carbonyl oxygen interaction with protons, which would make the carbonyl carbon more suspectable to nucleophilic attack; at a basic pH, the carbonyl carbon is more stable and less suspectable to attack.

Speaking of acidity, coolants most certainly turn acidic over time -- I dipped a relative's never changed 12 year old/120,000 mile old Toyota Pink coolant with a pH test strip and it came back with a pH around 5 or 6.

All that being said, it's probably easier to sleep at night by going with OEM instead of aftermarket if there are any doubts :).
 
Last edited:
Disclaimer: not a chemist, but was highly interested in chemistry and pretty good at chemistry in college.

I believe that the issue with 2-eha and harming of certain plastics and gasket materials is a valid issue, but it's more of an issue "in a vacuum."

I believe that Prestone uses 2-eha with confidence because they

a) use a lower concentration of it than in earlier, more problematic coolants

b) extensively buffer the coolant to prevent 2-eha from attacking plastics and gasket materials

The main issue of 2-eha attacking nylon 6,6 is valid, yes. The issue with nylon 6,6 is its susceptibility to hydrolysis. The hydrolysis is more favored in acidic environments than in basic environments. Coolant starts off as basic, that's why we have coolant pH test strips and usually we're looking for a value between 8 and 10 when dipping the coolant. An acidic coolant is one that needs to be replaced. I believe that on earlier cars, that used 2-eha, there were issues with air mixing with the coolant, which accelerated the breakdown of the ethylene glycol into acidic byproducts, which created a favorable environment for 2-eha to do its thing to nylon plastics. Something that's emphasized a lot in chemistry is the importance of pH in aqueous chemistry, and how pH can stabilize or destabilize molecules.

It seems reasonable that in a well-sealed cooling system, with minimal amounts of air intrusion, with a coolant that has a robust pH buffering package that keeps the coolant basic, and with a coolant that has a minimal concentration of 2-eha, that 2-eha would have minimal effect on nylon. An acidic pH would increase carbonyl oxygen interaction with protons, which would make the carbonyl carbon more suspectable to nucleophilic attack; at a basic pH, the carbonyl carbon is more stable and less suspectable to attack.

Speaking of acidity, coolants most certainly turn acidic over time -- I dipped a relative's never changed 12 year old/120,000 mile old Toyota Pink coolant with a pH test strip and it came back with a pH around 5 or 6.

All that being said, it's probably easier to sleep at night by going with OEM instead of aftermarket if there are any doubts :).
I agree, go with OEM. In the case of GM, it’s Dexcool with 2EHA. 😀
 
......All that being said, it's probably easier to sleep at night by going with OEM instead of aftermarket if there are any doubts :).
....Or 'imo', any aftermarket AF that doesn't use 2eha as inhibitor in its formula. All the "true" (matching vast majority OEM) Asian Phoat AFs are that way, eg, Zerex Asian, Peak OET Asian, Napa Asian, Pentofrost Asian. In the Universals, there's Peak Global Lifetime, what's left of Peak 10X and the new Peak Titanium AF. Taking into account last words, I have no doubts about any of them.

Speaking of Asian Phoat AFs, in this case Factory Fill Honda Type2, did a simple radiator d&f ~14 year interval and posted pics of findings. Pretty impressive, imo. https://bobistheoilguy.com/forums/threads/2007-honda-type-ii-factory-fill-pics.335946/
 
Back
Top Bottom