
Engine oil can reach a maximum temperature of 120 degrees Celsius. Normal operating temperature: The normal operating temperature of engine oil is generally between 70-90 degrees Celsius, with some localized areas being higher. However, it usually does not exceed the coolant temperature. At higher speeds, the temperature can rise to 100-110 degrees Celsius. But if it consistently exceeds 120 degrees Celsius for extended periods, an inspection is necessary. Effects of oil temperature: If engine oil temperature is too low, it hinders combustion and affects engine performance. Conversely, if the temperature is too high, it puts significant stress on engine components, especially oil seals and gaskets.

Last time I was stuck in traffic on a long drive, I noticed the oil temperature gauge had shot up to 120°C, so I quickly pulled over to take a break. The mechanic told me that conventional mineral oil can barely handle up to 130°C—any higher and it starts breaking down and losing effectiveness. It’s even scarier with modified cars on the track; some turbocharged engines can push oil temperatures to 150°C or higher, which is why race cars use specially formulated full synthetic oil. High temperatures not only thin out the oil but also cause rubber seals to degrade and leak. The worst-case scenario is cylinder scoring or bearing failure. My advice: keep an eye on the coolant temperature gauge during summer highway drives, and if your car has performance mods, it’s best to install an oil cooler and switch to a high-performance oil with a 40 or 50 viscosity for extra safety.

Only after playing racing simulators do you realize how crucial oil temperature is. For regular commuter cars, around 100°C is normal, but during aggressive driving, the oil pan temperature can hit 130°C. Last time I rode in my friend's modified GTR on the track, the oil temp gauge shot straight to 150°C – at that temperature, conventional semi-synthetic oil would've failed long ago. High temperatures thin out the oil, preventing proper oil film formation, which leads to dry engine friction and catastrophic failure. Performance cars must use full synthetic oil with high-temperature viscosity like W50, and adding an oil cooler system makes it even better. If you smell burning or hear valve ticking, pull over immediately to cool it down.

Old Zhang, my neighbor, only came to repair his truck after the engine oil burned out. Freight trucks often climb slopes continuously, causing the oil temperature to rise to 140°C. Ordinary 15W40 engine oil can't withstand temperatures exceeding 120°C. High temperatures cause the oil to oxidize and thicken, clogging the oil passages, and even scratching the bearing shells. I told him heavy-duty vehicles need CI-4 grade diesel engine oil, which can endure up to 135°C. Passenger cars are better off, but oil temperatures may exceed 110°C during summer traffic jams, so it's advisable to check the oil condition every 5,000 kilometers. If the oil turns black and thickens or the dashboard warning light comes on, immediate action should be taken.


