In Reply to: Re: 2N coolant posted by Select-O-Speed on October 28, 2020 at 08:33:20:
This is a lot like the ZDDP debate - lt has a basis in historical fact but chemistry is an evovling technology and you need to rely on good science not anecdotal stories from the web if you want to stay current. The problem has been known for some time. This rather dated SAE study is a good historical read as a starting point - you can get the actual study if you want to pop for the $50.
Long life coolant chemistry has and continues to evolve. What was true 10, 20, or 30 years ago may not be true today. The primary offender in early OAT products was the 2-Eha formulation pioneered by and still widely used by Prestone. Subsequent chemistry has replaced 2-Eha with other chemistry and most modern hybrid formulations (HOAT) are considered safe for use in older cars and trucks.
The bottom line is IAT coolant works just fine in older equipment but but has to be changed every two years or it too will damage your cooling system. If that is OK with you use IAT. But there ARE long life formulations that will last longer and protect just as well if not better than IAT in that equipment. And don't bet the mortgage or your cooling system on the color meaning anything - read and understand the label.
Solder Protection with Extended Life, Carboxylate-Based Coolants 2000-01-1979
Silicate-free, carboxylate based technology as typified by Texaco Extended Life Coolant (TELC) and Caterpillar Extended Life Coolant (ELC), both meeting Caterpillar's EC-1 Coolant Specification, offer excellent corrosion protection for commercial lead solders commonly used in the fabrication of copper/brass radiators and heater cores throughout the trucking industry. Results of laboratory testing using solders from commercial radiators manufacturers and extensive field coolant analysis compare extended life technology with the popular conventional coolant technologies.
In the laboratory, the effect of coolant concentration on solder protection is explored using the glassware corrosion test, ASTM D-1384. At concentrations ranging from 33% up to 75% the carboxylate technology offers comparable to superior protection when compared to the popular heavy-duty conventional coolant containing silicates and phosphates.
More importantly, however, real world field experience is gleaned from extensive coolant analysis. These analyses, representing a broad array of heavy-duty diesel engines using either conventional or extended life coolants, provide clear evidence of the superior solder protection offered by carboxylate technology. Coolant analysis from over 8000 engines is provided to relate coolant lead levels to coolant solder protection. As coolant concentration increases with conventional technology, the amount of lead found in the coolant sample also increases indicating the presence of active corrosion. By comparison, lead levels observed with extended life, carboxylate coolants remain low over the range of coolant concentrations observed. The low lead levels cannot be explained by solubility differences and indicate excellent solder protection at all glycol levels analyzed when using Extended Life coolant technology.Finally, examination of cooling system components taken from a truck with a million mile history on Extended Life technology confirms excellent solder protection over this extended period without the need for supplemental coolant additives as would be required if conventional technology were used.
And here is what Caterpillar says today about their current long life formulation which is recommended for ALL caterpillar equipment ever made:
New chemical technology for long life
Cat ELC incorporates an advanced formula technology with organic additive
corrosion inhibitors. Instead of nitrates, silicates, phosphates, borates, and
amines, Cat ELC contains mono- and dibasic organic acid salts for
maximum protection of the six basic metal alloys-copper, solder, brass, steel,
cast iron, and aluminum-found in most heat transfer systems. Some nitrites
and molybdates are added to help protect the iron components in the cooling
system, reducing steel corrosion and pitting effects