Extended Life Coolants/Antifreezes

Introduced back in the 1980s to save on maintenance costs and provide better protection than conventional coolants, heavy-duty extended life coolants (ELC) can last between 400,000 and 600,000 miles with the use of a one-time extender. In theory, it...

Arcy says there is a recommended procedure to follow when switching to ELC.

"Go through the testing, just like you would maintenance before you do anything," Arcy says. "Take a sample and look at it for clarity, check it for freeze point and check the nitrite level to understand the integrity of that system--you want to know if the thing only had 10 percent coolant in it, so its freeze point was barely below freezing or the nitrite level was extremely low, or there were particles and stuff in the system, you know you might have some problems down the road, because you're already starting out with a system that might have been compromised.

"If it checks out, we recommend flushing the system, filling it back up with 50-50, and changing over the coolant filter on it as well, but basically, you're done at that point."


For fleets with good coolant still on board, Arcy says a conversion fluid is the answer.

"Check the integrity of the system by taking a sample and making sure it's clean and no contaminants or anything in it, make sure the freeze point is in line, check the nitrite level, document all that," he says. "If that all checks out, then we have our conversion fluid, and what you do is drain a gallon out of the system of what they have in there, pour in the conversion fluid, run the system and circulate it so it's well-mixed in, then we recommend you again check the freeze point to make sure it's within limits, pull a sample to send in to us, then you're done. Put stickers on your system saying it's converted."

Chevron also has a conversion inhibitor package; a super-concentrate of their ELC inhibitors which is cheaper than doing a drain and refill, says Ulabarro.

"The safeguards are the conversion package has a pre-test and post-test," she says. "The pre-test allows you to determine if the coolant you're going to treat is in good enough condition to be treated from a freeze point perspective, a nitrite perspective and pH. Then you do the conversion and take a sample of the coolant and mail it in for analysis. That allows you to know that you treated the coolant correctly at the right level with the inhibitor concentrate, and it gives you a baseline to work off for future analysis, because coolant testing is not something that's very popular--oil testing is popular, but people don't think about doing coolant testing.

"A lot of customers think you can just throw something in there and you're fine," Ulabarro says. "Some customers throw something in there, they think they have ELC and ‘Guess what, I don't have to top off with ELC anymore.' Wrong. There's a lot of misinformation about how you need to follow up the conversion. It's kind of like losing weight and then thinking you can eat a hamburger every day for lunch; it's not going to work well."


While ELC clearly has its advantages, Ulabarro says for some fleets, it can actually be more trouble than it's worth.

"Fleets that have very bad maintenance and cannot control their top-up, I would not recommend an extended life coolant, because they'll pour anything in; any time, any place," she says. "That kind of fleet has a lot of cooling system problems and probably is not taking care of the cooling system very well. They need to use a fully formulated coolant where they have to test with a test strip every time and they have to add supplemental coolant additives and go through all that extra work and expense in order to at least maintain their cooling system to a certain level."

If a fleet does not have the maintenance capability to properly care for ELC, Ulabarro says they can do more harm than good. During a recent visit to train fleet technicians, she helped one fleet professional see the light.

"I told their vice-president, ‘I don't think you should be using extended life--you have no control'--and he looked at me like I slapped him in the face," she chuckled. "That's the kind of situation where you really need to look at the realities of what you have in your system and go from there. What happens is when they start using extended life coolants and start having failures, obviously they're blaming the coolant, but when you test the coolant, the biggest things are over-diluting with water and over-diluting with other technologies."

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