Cooling systems are one of those things people think they understand—until their engine overheats, their radiator clogs up, or their coolant turns into a thick, sludgy mess.

For years, we’ve heard the same misconceptions floating around: “All coolants are the same,” “Water is just as good as antifreeze,” or the classic, “If it’s not freezing outside, I don’t need coolant.” That’s why EPARTRADE brought in an expert to set the record straight.

Cooling technology has evolved. What worked in 1975 won’t cut it today. And making the wrong choice? That can mean blown head gaskets, destroyed radiators, and thousands in repairs.

Joe Long, Senior Field Technical Trainer at Old World Industries, is one of the leading experts in cooling system technology. In a recent EPARTRADE webinar, he tackled coolant myths head-on and provided crucial insights that every shop, racer, and car owner needs to hear. Let’s break it down.

Myth #1: “All Coolants Are the Same”

If you’ve ever picked up a jug of coolant and thought, “Eh, color doesn’t matter. I’ll just pour this in,” you might want to rethink that.

Joe Long, Senior Field Technical Trainer at Old World Industries, put it plainly, “All coolants are not the same.” Cooling systems are designed with specific chemistry in mind, and that chemistry varies widely depending on the manufacturer, region, and even fuel type.

Here’s the breakdown:

• Pre-1995 cars used a green, silicate-based coolant that protected copper and brass.
• GM introduced Dex-Cool (orange) in 1995, an organic acid technology (OAT) that lasts longer but isn’t backward compatible.
• Heavy-duty diesels often use fuchsia (pink/purple) coolants with different corrosion inhibitors.
• OEMs have their own formulas—BMW (blue), Toyota (red), Ford (yellow)—and they’re different for a reason.

Bottom line: Don’t assume all coolants are interchangeable. Color is just a dye—it’s the inhibitor package inside that matters.

Myth #2: “Water Works Just Fine”

On paper, water is the best heat transfer fluid there is. But using only water in your cooling system? That’s a recipe for disaster.

Joe Long made this clear, “Even though you’re not concerned about freeze, you need to be concerned about other issues in a cooling system that doesn’t use glycol.” 

Here’s why:

• Water causes corrosion — coolant contains inhibitors that protect metal components.
• Water promotes bacterial growth, turning your system into a breeding ground for black sludge.
• Water boils at 212 degrees Fahrenheit, while a 50/50 mix raises the boiling point to 265 degrees.

The right mix?

• 50/50 glycol-water mix: the industry standard.
• 40 percent glycol if you’re in a mild climate: still protects against corrosion.
• Never go over 60 percent glycol: too much and you lose heat transfer efficiency.

Bottom line: Water alone is a bad idea. Always use the right coolant-water mix.

Myth #3: “Universal Coolants Work for Any Car”

Ever seen a bottle labeled “All Makes, All Models (AMAM)”? Sounds great, but let’s be real—there’s no such thing as a true universal coolant. 

“There are products that are marketed as what we call AMAM, all makes, all models. So that’s for the fleet that maybe does run, you know, GM and Chrysler and Ford,” Joe Long explained

Here’s how AMAM coolants actually work:

• They’re designed for fleet operations, where shops don’t want 10 different coolants on the shelf.
• They usually contain inhibitors that work well for most post-2000 vehicles but may not meet specific OEM requirements.

If you drive a BMW, Toyota, or Ford, their factory-fill coolant has specific additives for seals, gaskets, and engine materials.

Bottom line: If you want to play it safe, use the coolant your car was designed for.

Myth #4: “Race Cars Use the Same Coolant as Street Cars”

If you track your car, you need to pay attention to this. Race tracks ban ethylene glycol because it makes the track dangerously slippery. One spill, and you’ve turned the circuit into an ice rink.

“We don’t want to spill glycol on a racetrack because glycol is going to saturate the asphalt, and it will make the track extremely slippery,” Joe Long confirmed.

Instead, most racers run:

• Water with Water Wetter: A surfactant that improves heat transfer and adds lubrication.
• Some glycol in the offseason: Prevents bacterial buildup when the car sits.

Bottom line: Race cars and street cars use different cooling strategies. Know the rules before you hit the track.

Cooling systems are more advanced than ever, and the wrong choices lead to failure.

The best approach is simple: Use the right coolant for your vehicle. Test your coolant regularly to avoid costly repairs. Store race cars properly in the offseason to prevent bacteria growth. Dispose of coolant safely, never dump it down the drain.

Cooling technology is constantly evolving, especially with hydrogen and electric vehicles on the rise. What worked 30 years ago won’t cut it today.

Want to avoid blown engines and cooling failures? Stick to facts, not myths.