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Does anyone know what the (more or less) acceptable standardised range is, for the oil temperature of a car engine?

I understand that 40-120 degrees C, seems to be the acceptable range for the engine coolant temperature, but whats the range for oil temperature? I have searched and searched for this, different sites give me different ranges based on the engine and oil type.

Thanks for your time, Dan.

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  • Do you mean when the engine is at running temperature? Or, when the engine is not in use but ready to be used...
    – Solar Mike
    Feb 19, 2017 at 12:24
  • @SolarMike Yes (I guess), as I'm talking about the range displayed on the drivers dashboard. So for the coolant gauge, it starts from 40°C and ends at 120°C. So what would be the equivalent for the oil gauge? Feb 19, 2017 at 12:26
  • Most vehicles don't have a temperature range for oil, but rather a pressure range. Also, if there aren't numbers located on your gauges, the gauge is more or less a placation device to show the driver something is going on. Even when there are numbers, the accuracy of the numbers should be considered suspect. Feb 19, 2017 at 14:07
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    From my experience, oil t follows water temp closely. Fitted a gauge to both a v8 and 4 cyl turbo diesel. The range on the gauge affects the accuracy - it can be the same as the one you quote which means the accuracy is poor. A gauge which has a short scale - working over the useful range such as 60 to 120 gives a more accurate indication. Often the oil filter housing had a cooling coil fiited to help control the oil t especially if there is not much airflow around the sump.
    – Solar Mike
    Feb 19, 2017 at 14:53
  • Oil gauges typically range from 50°C to 150°C. Normal temp should be 90-110°C, a little more when racing. Significantly above 120°C would make me suspect some defect for a normal car; 140°C would be my absolute red line.
    – JimmyB
    May 22, 2017 at 11:05

2 Answers 2

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Operating temperature of most modern car engines is ~90C (about the same to the thermostat opening temperature) and oil temperature in the sump will be around 10C less than that.

More and more modern cars tend to increase engine operating temperature for increased engine efficiency and reduced emissions, hence they increase oil temperature in the sump.

So in general oil temperatures in the sump are less or in par with engine coolant temperatures.

But oil can reach very high temperatures for a very short time in the hottest parts of engine (around piston rings).

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  • To support this answer, my measured oil temp runs up to 98C per logged output in a 2008 Audi A4 2.0T
    – David Sain
    Sep 23, 2018 at 18:09
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For non-synthetic motor oil, the traditional approach is to try to hold oil temperatures between 110C and 125 degrees (~230-260F). For full synthetic motor oil, maximum can exceed 300 degrees. In all cases, less than 100C (212F) will cause water buildup in the crankcase.

See this link for more information.

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