How to Distinguish Antifreeze Engine Oil?

[JoyDella]

To distinguish antifreeze engine oil, you can freeze the oil in a refrigerator and then observe its antifreeze viscosity. Below is an introduction to the classification of engine oil: Classification by oil composition: According to the composition of engine oil, it can be divided into full synthetic, semi-synthetic, mineral synthetic, and mineral oil. Oil model: On the packaging of engine oil, you will find markings such as 5w30, 0w20, and 5w40, which indicate the model of the oil. The "w" stands for winter, meaning that if there is a "w" in the marking, the oil can be used in winter.

[VonCatherine]

When I help friends choose engine oil, the most straightforward method is to look for the low-temperature fluidity label on the packaging. Check if the oil container has specifications like SAE 0W-20 or 5W-30—the smaller the number before the 'W,' the better it performs in freezing temperatures. For example, the 0W-40 I picked for my neighbor last winter remained fluid even at temperatures below -30°C. Additionally, I always check the manual for certification standards. For friends in northeastern China, I specifically look for antifreeze types with ACEA C3 certification. Nowadays, many full-synthetic oils directly feature a snowflake symbol labeled 'Suitable for Extreme Cold.' By the way, high-quality antifreeze engine oil pours like golden honey with moderate viscosity—it won’t solidify into chunks even after a night in the freezer.

[SawyerLynn]

In practical use, I found that antifreeze engine oil performs exceptionally stable during seasons with large temperature variations. I remember when driving the old Jetta, switching to conventional oil made the engine wheeze like an old cow on cold winter mornings, but after switching to 5W full synthetic, the startup became noticeably smoother. This type of oil has higher purity base oil and can still quickly cover component surfaces even in sub-zero conditions. Nowadays, when selecting oil, I usually check the pour point parameter first—standard antifreeze types typically indicate they remain liquid and flow at temperatures as low as -40°C. Additionally, the low-temperature anti-gelling agents added to the formula prevent sludge formation, and even after running 8,000 kilometers, the dipstick still shows a translucent amber color.

[Noelle]

In the past, I often helped car owners test the low-temperature performance of engine oil at repair shops. The simplest method was to pour the oil sample into a glass bottle and place it in the freezer compartment of a refrigerator. Conventional mineral oil would become as thick as maltose at -10°C, while qualified antifreeze engine oil could still flow smoothly at -25°C. Nowadays, high-end antifreeze oils even contain special ester-based formulations. For example, Volvo's original 0W-20 oil can completely cover the bottom of the bottle within three seconds when the bottle is tilted, even after being frozen overnight. When purchasing, be sure to avoid obscure off-brand oils with unclear labeling. Genuine antifreeze engine oil must have clear SAE grade markings and the manufacturer's anti-counterfeiting code on the outer packaging.

[DiVivienne]

From a compositional perspective, most antifreeze engine oils utilize Group III or higher hydroprocessed base oils. These molecular structures are less prone to crystallization at low temperatures, with viscosity-temperature indexes nearly 40% higher than mineral oils. Laboratory data shows that genuine 0W-grade oil maintains a kinematic viscosity below 6,000 centipoise at -35°C. While some market oils claim 'all-season use,' many solidify at -18°C in actual tests—it's best to look for European standards like ACEA C2/C3 certification. Northern vehicle owners should verify oil grades before winter, as the cold-start protection difference between 5W and 0W oils can reach 15°C.