Checking your car's antifreeze (also called coolant) level is a simple but vital part of routine maintenance. You can do it in under five minutes. The safest and most accurate way is to check the level in the translucent coolant overflow reservoir when the engine is completely cool.
Locate the reservoir under the hood; it's usually a white plastic tank with a hose leading to the radiator and has "Full" and "Low" markings on the side. The coolant level should be between these two lines. If it's near or below the "Low" mark, you need to add a 50/50 mixture of antifreeze and distilled water. Never open the radiator cap when the engine is hot, as the system is under extreme pressure and can release scalding fluid.
It's also smart to check the coolant's condition. Fresh coolant is typically bright green, orange, pink, or blue. If it looks rusty, muddy, or has particles floating in it, it may be time for a system flush. Most manufacturers recommend replacing coolant every 30,000 to 100,000 miles, depending on the type used.
| Coolant Type (by color/common name) | Typical Replacement Interval | Key Characteristics |
|---|
| IAT (Inorganic Additive Technology) - Green | Every 2 years or 30,000 miles | Traditional formula, less common in newer vehicles. |
| OAT (Organic Acid Technology) - Orange, Red, Pink | Up to 5 years or 150,000 miles | Common in General Motors, Volkswagen, and others. |
| HOAT (Hybrid OAT) - Yellow, Turquoise | Up to 5 years or 100,000 miles | Used by Ford, Chrysler, European brands; a hybrid formula. |
| PHOAT (Phosphated HOAT) - Blue, Pink | Up to 10 years or 150,000 miles | Often found in Asian makes like Toyota, Honda, Nissan. |
Using the wrong type of coolant can damage your engine's cooling system. Always consult your owner's manual for the specific fluid type and maintenance schedule for your vehicle.
