Knowing Your Coolants

It used to be so easy when it came to automotive coolants.
As a jobber, you simply had to carry a universal coolant, and that was enough for your service provider customers. You also knew that coolants would be changed twice a year, once in the spring and once when winter arrived. It was a steady revenue stream.
Then things got complicated. With newer vehicle technologies coming with more complex cooling systems, there was a proliferation in the kinds of coolants to be used. And the twice-a-year coolant change began to slowly disappear, replaced by longer-life coolants.
Jobbers now need to carry a wider range of coolant SKUs, and front-line staff need to be a lot more knowledgeable about coolants and how to match them correctly to vehicle makes and models.
Mike Adema, owner of Jake’s Auto Service in Georgetown, Ontario, has seen this change firsthand. “I’m specifying to my jobbers what kinds of products I’m looking for and what my clients want from me,” he says. Gone are the days of the universal coolant for his service operation. “Typically, when it comes to coolants, I’m looking for an OE-equivalent product, not a ‘one-size-fits-all’ product,” he continues.
Adema adds that today’s vehicle owners don’t often know what is the right coolant for their vehicle and will defer to the shop technician and service advisor to make the right call. And in turn, the technician and service advisor will rely on the jobber and its front-line staff to help them make the right choice.
Greg Bahm, part-owner of Bahm’s Auto Service and Supply in Kerrobert, Saskatchewan, says that most vehicle owners today will follow what is outlined in their owner’s manual. In today’s vehicles, it will likely list a set of specific coolant types to be used. There can be no substitutes. If someone does ask for a universal coolant, it is likely for an older vehicle, not one of today’s new vehicles.
Karen Insko, Valvoline’s global product manager, coolants and chemicals, agrees that technicians and service advisors must first go to the owner’s manual to find out what coolant is to be used with the vehicle. The days of matching coolants by colour, a once common way of deciding on what the right coolant was for the vehicle, is to be avoided. “Match based on the original chemistry used in the vehicle production,” Insko advises. “If a car rolled off the assembly line filled with long-life OAT coolant, replace it with an OAT coolant. Better yet, look for a coolant that carries the OEM’s approval, not just a ‘Recommended For Use’ application for the vehicle.”
Jake’s Auto Service’s Adema says mismatching coolants to vehicles can create problems. While those problems will not be immediate, he says that today’s vehicle coolant systems are designed to work with specific coolant chemistries. Over time, the wrong coolant will begin to adversely impact the vehicle’s coolant system.
Both jobbers and service advisors or technicians need to remember that coolants come with specific additives that are matched to specific cooling system designs and the materials used in the cooling system construction. Some additives are made to prevent corrosion; others are made to be compatible with the rubber and plastic used in the system, such as those in water-pump seals. If the wrong coolant is used, it could lead to corrosion, which can cause clogging in the cooling system, and other problems.
“Vehicles on the road today are more complex in design than ever before, and require specific chemistries to perform at optimal levels and meet stated service intervals,” says Valvoline’s Insko. “Cooling systems are tested and known to work with specific coolants. Jobbers should always recommend replacing or topping off the coolant with the same chemistry as the vehicle was originally filled with.”
Insko says jobbers and service operations need to remember that a vehicle is a significant investment for today’s consumer. “[Coolant system] damage can be latent: it may take months to occur, and it is often not associated with poor coolant performance. People can mistakenly conclude the engine part simply failed, without realizing that last year’s coolant change was the reason for the delayed failure. Mismatching coolant chemistries can result in anti-synergistic mixtures, leading to accelerated corrosion and eventual cooling system and component failure.”
“It is not necessary to stock multiple vehicle-specific antifreeze/coolants within a specific class of vehicle,” says Colin Dilley, Ph.D and vice-president, technology with the Prestone Technology Center. “Good quality coolant has to stop corrosion and prevent freezing and boiling in all manufacturers’ cooling systems, and it also needs to be compatible with all other coolants.”
Making the Right Coolant Choice
Jobbers are often the first point of contact for service advisors and technicians when it comes to answering coolant questions and for advice on maintaining cooling systems.
Jobbers should remind service advisors and technicians that coolant levels need to be checked at each oil change. That seems simple enough, but many will forget to do so, relying instead on checking when a certain number of kilometres have passed before checking coolant levels.
Low levels can lead to overheating. If you notice that the cooling system needs too-frequent topping off, a pressure test is recommended to see if there is a leak in the system. Immediately replace any leaking hoses or failing clamps and components that are discovered. While it is recommended that coolants be changed according to the vehicle OEM’s maintenance intervals, it is still a good thing to check the coolant itself and the mixture levels. It’s surprising how many vehicles on the road have not had their coolants inspected or changed throughout the life of the vehicle. That is usually because the vehicle owner has said not to bother, which is a grave mistake.
“Based on the original chemistry, some coolants protect longer than others,” Insko says. “For example, organic acid technology (OAT) coolant has a longer service life – five years or 240,000 km (150,000 miles) – than traditional inorganic acid technology (IAT), which has a service life of three years or 80,500 km (50,000 miles).”
OAT coolants were first used in Europe before coming to North America. These coolants come with inhibitors that are made to last longer before breaking down. OAT coolants should not be used with older vehicles that operate with copper-and-brass radiators, but only in vehicles that use aluminum or plastic in the cooling system.
General Motor’s DexCool and other coolants use organic inhibitors called sebacate and 2-EHA (2ethylhexanoic acid) that is best suited for cast iron engine blocks.
HOAT (hybrid organic acid technology) is popular with European automakers, as well as such American OEMs as Chrysler and Ford.
“It is not recommended to dilute below 55% coolant in North America,” says Valvoline’s Insko. “Freeze protection is diminished with added water and the additives are also diluted, resulting in the potential for inadequate protection. This is a particular concern in the winter due to freezing.”
“When recommending antifreeze/coolant, first ensure an extended life five-year coolant is recommended versus a two-year, typically green, formulation,” adds Prestone Technology Center’s Dilley. “Vehicles have been factory-filled with extended-life coolant for at least the past 15 years, and it is important to match the same technology the engine was designed for. Corrosion protection is becoming increasingly important as engines become more sophisticated.”
When it comes time to replace coolant, when it has reached either the end of its useful life or the recommended change interval by the vehicle maker, it is time for a full coolant flush. “When the recommended service interval calls for a coolant flush and fill, using a quality radiator cleaner and flush chemical will help remove any accumulated deposits that may have formed in the cooling system,” says Insko.
This sometimes causes hesitation amongst some service technicians, who believe that cleaners cause more problems than the cleaner claims to fix. However, neglecting regular flushed and coolant replacements is a costly mistake.
“Remind technicians to ensure they do a coolant check, using a refractometer, and showing customers their coolant so they can see any particulates. Always provide the best products to customers so you don’t have them coming back to you later,” says Dilley.
“Cooling system failure is one of the most common causes of mechanical engine failure,” continues Insko. “Given the investment consumers make in their vehicles, the cost of maintaining the cooling system is well worth it. Over time, all coolants begin to diminish in their protective qualities. Even with regular top-offs, deposits can form that lessen the effectiveness of the cooling system. Proper maintenance includes keeping the system filled, maintaining proper freeze protection, and regular flush-and-fills with the right chemistry designed for the vehicle. The more consumers understand the value of using the right coolant, the better the sale opportunities for service operations and jobbers.”