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 would seem only a matter of time before ELCs become the standard, but sometimes what looks great on paper is not always as effective in the real world. Industry experts say while these coolants can be extremely effective and save significant money, they are not necessarily right for every fleet.


For fleets with good maintenance programs, ELC has many advantages, says Chevron direct channel marketing manager Carmen Ulabarro, but none more significant than reducing maintenance times on cooling systems.

"They don't have to add additives, they don't have to test it with test strips every three or four months, they don't have to keep supplemental coolant additives in their shops, and basically they can use one coolant for everything," she says. "Extended life coolants work better as far as heat transfer agents, because they lack some of the inhibitors that actually reduce heat transfer that are found in fully formulated coolants. An extended life coolant has no abrasives, so water pumps last longer. There's no plugging with extended life coolants; there's nothing in the coolant that would allow for plugging, you don't have to refortify them every four months or so."

One of the main problems coolants help prevent is pitting of cylinder liners, which can cause coolant to leak into the engine and shorten its life, but how that is accomplished depends on the additives used. Shell OEM Technical Manager Dan Arcy says in a conventional, or fully-formulated setup, the 50-50 glycol and water mix requires periodic additions of supplemental coolant additives (SCA) to protect the liners; generally every 15,000-25,000 miles, depending on what the technician finds.

"They're going to have to find out how much of that SCA is in there still, and top off and bring it back up to specifications," he says. "That's the big difference between them (and ELC), and that's where a lot of the reduced maintenance and reduced costs comes from--it's the ability to not have to add additional SCA."

With ELC, the only time you will need to add an extender is at 300,000-miles, Arcy says, which should bring the life of the coolant up to 600,000 miles. Less maintenance is only one of the potential advantages for ELCs, though.

"We see increased water pump life, cleaner radiators, because you don't see the SCAs plating out in there," Arcy says," And you get the better heat transfer, which, with a lot of newer engines running hotter, is a benefit."


Since many fleets are switching to ELCs, they are asking OEMs like Freightliner, PACCAR, Volvo/Mack and International to factory-fill new trucks with extended life coolants, Ulabarro says. For fleets that haven't yet, she says there are plenty of good reasons to give them a try.

"When you look at how temperatures are going up, you're looking at the 2010 engines, you're looking at trying to extend oil drain intervals, you're trying to improve fuel economy, and we know the biggest factor in fuel economy is really the driver," she says. "The higher, better, more technologically advanced fluids you have in your system, the better your fuel economy is going to be. If your coolant is working effectively and transferring heat effectively, your oil will be able to last longer. If your oil doesn't thicken, it will take less energy to start up your truck. All of these things are a circle, and you've got to get everything in there working correctly.

"When you're looking at (ELC), you need to think about the benefits it can give you outside of long-term, ‘How am I going to reduce my maintenance?" Ulabarro says. "There are other things in this whole equation that really add up as a benefit for extended life coolant that you may not be able to add a dollar sign to, because it's variables--depending on the truck, how it's run--but all those little things add up, and also the reduction in maintenance that you have to do with an extended life coolant, as far as parts."

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."

Sometimes, it's not that a fleet has poor maintenance practices, it's just the nature of their business that lends itself to avoiding ELC, Ulabarro says.

"Fleets (with) leasing operations have a hard time getting their trucks back into their shops on a regular basis; those might be fleets that have to take extra care," she says. "You've got to have the kind of operation where you can control your top-ups, or you see your trucks on a regular basis, and when those trucks do come in you can test that coolant effectively and know whether it's extended life or whether they've added too much of something else and you have to either re-fortify with an extended life package or if you just drain and refill the system."


Chris McKenzie, director of marketing for The Penray Companies, Inc., says fewer people have replaced conventional coolants with ELCs during the past few years, citing a MacKay & Company survey showing that in 2005, 46 percent of replacement coolant was ELC, while in 2006 that number dropped to 36 percent. He says the reason is fleet professionals may be finding out the promise of ELC is more rooted in theory than in practice.

"They'll say it's good for the life of the engine and at the 300,000-mile mark you need to add an extender and there's no other treatment necessary," he says. "That's the attractive part--you never have to touch it and a lot of people feel that the less time a mechanic spends on a vehicle, the less that can go wrong. The problem happens when you start thinking about it in reality. Cooling systems leak--every single one of them--so if anything should go wrong with that system, the odds are pretty good it has something to do with the cooling system.

"And if you change the mixture of the extended life coolant by 10 percent, you've lost your extended-life properties," he says. "Then you either have to drain, flush and refill, or you can kind of start treating it like a conventional coolant. So that's the unattractive portion--you have to actually pay attention to (your cooling system) and work on it. We see it all the time, where people are trying to convert to a conventional system because they don't want to have to drain and flush it out, spend the time and the energy to take the truck off-line and then have to pay for 12 gallons of new coolant and reload the system."

McKenzie says some fleets are hesitating to move to ELC is simply because what they've got already works.

"Conventional formula antifreeze has always worked, still continues to work and is an absolute proven entity in the market," he says. "There is no reason to spend more to get an extended life coolant that's unproven and unforgiving."

Add to that the confusion across the industry about all the varieties and colors of ELCs and McKenzie says sometimes, sticking with a reliable solution like conventional coolant makes sense to fleets.

"When you're working with ethylene glycol and water and a conventional SCA package, you can contaminate the system a little bit more, you can put different brands of things in there; you can top off with the wrong amount of antifreeze and still regain balance if you're paying attention," he says. "Whereas with an extended-life coolant you don't have that flexibility. If you don't treat the system properly--regardless of what's in there--you can have potential disaster."


When cooling systems are not properly maintained, it causes a chain reaction of problems with other systems like water pumps, pressure gauges and gaskets, McKenzie says.

"It's just unbelievable the number of things that go wrong," he says. "Pumps are very susceptible to problems--they always have been and probably always will be. Mechanics hate them; they go through a ton of them, and they should have a longer life cycle than they do, but if you don't pay attention to your cooling system, it's not going to change."

Ulabarro says the "huge" disconnect between proper coolant maintenance theory and actual practice is hard to fathom.

"There are stats that say that 40 percent of the time a truck fails, it's due to the cooling system--if you could get rid of that 40 percent, wouldn't you want to do that?" she says. "(Instead) you throw coolant in there and you leave it in there until something breaks. Technicians just haven't made the correlation between the coolant and how important it is to that whole system, because the coolant regulates--to a much greater degree than the oil--the temperature."

During a recent training session, Ulabarro found an example of just how little some fleet professionals know about their coolants.

"I was guaranteed the only coolant in that shop was an extended life coolant, and guess what?" she says. "I found three different coolants. Sometimes headquarters has no idea what's going on at the shop--I had a discussion with the guys, and they get different information coming from different people, and what complicates things are a lot of OEM manufacturers' reps promoting their fluids, (then) there's the people who are more on the fully formulated, conventional products and there are companies that are selling (ELC)."


Properly maintaining coolant systems just takes some common sense and consistency. Ulabarro says there are steps technicians can take to make sure things are running smoothly. To reduce any possible confusion, she suggests displaying written procedures in the shop.

"If people see it and they have it in writing, there's no question or confusion," she says. "Test the freeze point, adjust it if it needs to be adjusted--top off with the extended life coolant that's in there, because there are different formulas for extended life coolants. If the freeze point is fine, you look for clarity in the coolant--make sure there's no oil or floating debris, it's not milky or anything. I usually have them have a bottle of reference coolant--just a clear glass bottle with some fresh coolant in it, and I have them draw a sample and match it up."

Arcy says having the correct type of pre-mixed coolant on hand, in the shop and on the vehicles, can go a long way in preventing problems--use the wrong coolant, and you could be back to square one.

"If you compromise the system by adding too much fully formulated to an extended life system, you'll have to start treating it as a fully formulated system, but there is no problem as long as you don't contaminate it by more than 15 percent," he says. "So in a system that holds 12 gallons, if you accidentally one time put in a gallon, you're still going OK. If you end up (adding) two gallons, you have three choices: You can take and treat this system as a conventional system and add SCAs, you have the ability of draining it, flushing it and filling it up with extended life, or go to a conversion fluid."


Penray's McKenzie says the entire industry has much work yet to do to educate fleet professionals about the importance of cooling systems, because a lack of knowledge can become very costly.

"It boggles my mind that people will spend $120,000 on a really expensive brand-new truck, and they'll know everything about it except what type of coolant is inside," he says. "You want to make sure people know to take care of cooling systems--it's vital--it's not a blow-off thing."

As important as cooling systems are, ultimately you want your technicians to work with your vehicles' coolant systems--not fight them. And if the realities of your shop make using ELCs more trouble then they're worth, cutting your losses and going with conventional coolants might be your best bet.

At the same time, if raising the bar in the shop and ensuring that your technicians take the time to properly maintain these systems is your goal, setting up your fleet to use ELCs can end up saving considerable amounts of time and money in the long run.

Is your fleet ready to take the leap?