Coolant temp vs oil temp
- Thread starter Whammo
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In normal flat freeway driving if your coolant is 195 your engine oil is probably slightly higher but it can vary based on:
actual vehicle, outside temp/weather, engine load, speed etc.
example: my 2015 forester as measured by where ever the oil temp sensor was..
would run 210-235 in normal highway driving.
actual vehicle, outside temp/weather, engine load, speed etc.
example: my 2015 forester as measured by where ever the oil temp sensor was..
would run 210-235 in normal highway driving.
What car?
Oil temp varies hugely with load and can be below coolant temp or above.
Oil temp varies hugely with load and can be below coolant temp or above.
In what vehicle doing what work in what conditions? My 2004 F150 with the 5.4 would barely hit 175 on the oil temp after an hour of running with a light load in temps below around 15 degrees... Part of why the cap was prone to showing milky stuff in the winter...
JHZR2
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Would say that coolant temp would usually tend to rise faster than oil.
This may not always be the case.
This may not always be the case.
Oil might be slightly hotter than coolant.
An exchanger’s fluid should run cooler than the media which is being cooled in order to dissipate heat effectively as a general rule. By design the oil will be slightly warmer at operating temperature.
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When everything is at normal operating temperature.. yes, I would agree with that, though it is not an absolute..
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In the summer the oil warms up faster also.. does it do so faster than coolant? You'd need a scanner to see
I'll have to see if torque can access the coolant temp on the Taos. I know the oil temp seems to run around 200 +/- 10 or so pretty consistently once up to temp. Of course I haven't had a chance to run it in summer temps so that might make a difference. If torque works I'll see how much of a difference there is. Considering it has an oil-water cooler I'd imagine it isn't too far off.
Majority of oil coolers use coolant to cool the oil, and while the engine is warming up, the coolant is heating the oil.
That should tell you everything you need to know.
That should tell you everything you need to know.
Where they separate is at high rpm operations. There is some very good data on this forum. The OP can search oil temperature in the search function. Some vehicles like a lot of Volkswagens and Ram products have oil temperature readouts. Lots of good data.
Mostly because they had a long oil filler neck that was higher than the valve cover. Vapor gets trapped in that area
I *love* my coolant/oil/trans temp readout on my Ram. Probably too much. But I'm always surprised how slow the transmission temp is to come up to the 190F mark. Takes a solid 20min in chillier weather, and half that in hot weather.
I have to plug in a scanner to see intake/ oil/ coolant/ trans temps. The SS has a pretty dead on Trans and coolant gage cluster. (No block oil temp) But a block over-temp above 260°f on rad coolant immediately zeroes out the OLM and it limps with DIC message of "CHANGE OIL NOW".
Mum's '13 impala hides it, but plugin scan shows it all, even catalyst temp.
For the first 15~20 mi. on either, the oil temp lags behind coolant temp, especially on the Impala.
They come in line with one another after those 20 or so miles, but with casual highway load, both have sump temperatures exceed coolant temps. Eventually the trans oil temp slightly exceeds coolant too, rising but stable under water boiling points. (About 200°f)
My educated "guess" over the years I can safely say that no matter the application, oil sump temps exceed engine/ coolant temps by at least 75 or more degrees if the engine is healthy. There may be localized oil temperatures especially if you street romp or sport/ race drive that further age oil faster.
I own, drive, maintain GM products and change early. I dump and refill @ 15% life of possible. I only saw "CHANGE OIL SOON" on a vehicle my mother owns once... but you know... boomer but beloved mummy that's not at all a car gal. ^.^
Mum's '13 impala hides it, but plugin scan shows it all, even catalyst temp.
For the first 15~20 mi. on either, the oil temp lags behind coolant temp, especially on the Impala.
They come in line with one another after those 20 or so miles, but with casual highway load, both have sump temperatures exceed coolant temps. Eventually the trans oil temp slightly exceeds coolant too, rising but stable under water boiling points. (About 200°f)
My educated "guess" over the years I can safely say that no matter the application, oil sump temps exceed engine/ coolant temps by at least 75 or more degrees if the engine is healthy. There may be localized oil temperatures especially if you street romp or sport/ race drive that further age oil faster.
I own, drive, maintain GM products and change early. I dump and refill @ 15% life of possible. I only saw "CHANGE OIL SOON" on a vehicle my mother owns once... but you know... boomer but beloved mummy that's not at all a car gal. ^.^
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