What are the causes of high oil temperature in a car?
2 Answers
There are two main reasons for high oil temperature in a car: 1. High engine load: Excessive residual heat is generated, leading to high oil temperature. This may be due to improper gear usage or heavy vehicle load when climbing hills, as the heat produced by the engine in a short period exceeds the cooling capacity, causing the oil temperature to rise. 2. Poor cooling system performance: A malfunction in the cooling system prevents the dissipation of excess heat. This could be because the engine oil has aged and can no longer transfer heat efficiently, or because the coolant level is insufficient, reducing the cooling capacity. Additionally, low vehicle speed may result in insufficient airflow through the radiator, preventing heat from being effectively dissipated into the surrounding environment.
I've been driving for over ten years and often encounter issues with high oil temperature. The most common problems are with the cooling system, such as the radiator being clogged with willow catkins or insects, the fan belt breaking, or the coolant leaking completely. There are also oil-related issues—if the oil viscosity is incorrect or the oil pump fails, lubrication can't keep up, and the temperature spikes. Last summer, during a long-distance drive, I faced this issue and found that the radiator had too much scale buildup. Driving habits also matter; prolonged overloaded uphill driving or aggressively stepping on the accelerator with the AC on in hot weather puts a lot of strain on the engine. For older cars, it's important to watch the thermostat—if it gets stuck, the coolant won't circulate at all. Once the temperature gauge warns you, pull over immediately and turn on the heater to dissipate heat. Pushing through can lead to engine seizure.