Yes and correct, no reason to worry about this or make any changes but folks keep saying ambients don't impact oil temps...they do. And at 115 F I'd predict 230 For so oil temp and that's just cruising along...stand on it like at the track and this is an issue.
Keeping cool
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My experience, over five years of driving a turbocharged car with an actual oil temp gauge, was very different.
In temperatures ranging from below zero to 100F, the oil temp was consistent, unless, and this is important, I heat loaded the engine with heavy turbo use.
So, 0F, and the oil temp was 85C. 100F and the oil temp was, yep, 85C.
But, in 10F, climbing up to the Eisenhower Tunnel, I would see 90-95C oil temp as the turbo heated up the oil.
Load mattered far more in that car than ambient.
It then is likely due to how my VW cools the oil with a coolant to oil heat exchanger b/c all my data were cruise control on at 70mpy/very low load. Load also matters in mine clearly as track use will peg it up to 272 as the highest I've seen.
The car to which I was referring, a 1985 Volvo 245 Turbo (manual, by the way, great mountain car) had an oil to air cooler with a thermostat. So, clearly, the thermostat opened at 85C. Which was what the service manual stated. And clearly, there was enough cooling capacity to handle easy cruise on a hot day.
I think that there must be performance differences in how the oil cooler is sized, and plumbed. More area vs. less internal to the cooler. Oil to air vs. oil to coolant. I’m surprised there was any variation in yours, I would have thought that under low load, the oil would stabilize at coolant temperature.
I don’t have a way to measure oil temp on this car, but I just upgraded the oil cooler on my daughter’s XC90. It’s an oil/coolant design. Much thicker ”sandwich“ on the new one (right) means more heat exchanger area. A bolt on upgrade, using a diesel part in place of the original part, so, all factory fittings.
I would love know if it makes any difference. Clearly, Volvo thought the diesel needed better oil cooling, but since I wasn’t able to measure “before” I would have no data to know if this made a difference. My goal in upgrading is to ensure consistent oil temp over a wide variety of operating conditions.
The issue may be that on mine, there is no oil thermostat that I'm aware of. Oil temps on the MQB/MK7 VWs are very talked about topic in the track groups. Folks adding oil coolers, hood vents, etc. to try to manage it.
Havent graphs been posted here showing kinematic viscosity at different temperatures? Viscosity at 200 versus 220 being roughly the same as going from an xw20 to an xw30? Similar to the OP switching to a 5w30 from a 0w20 giving a more similar kinematic viscosity as the engine runs hotter oil from ambient temps
Shear heating in the bearings perhaps. But not sump temperature. No sump runs 25 degrees hotter from a single grade increase.
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Yeah.. there's no way there's a 25 degree delta from a single grade increase. That would bring the usual 0W-20 oil that used to be in my BRZ that ran at 230 F down to 180 F on the 0W-40 that's in there now, which isn't the case.
Agreed. I said it confusingly but I'm referring to the kinematic viscosity cruising down the highway with warmer ambient temps and 5w30 in the sump being similar to cruising down the highway in lower ambient temps with 0w20 in the sump.
I've seen maybe 3-5 degrees warmer oil temps from running thicker oil in my vehicle similar to OP vehicle. But this is my observation and difficult to prove as I am not a lab or controlled environment.
I saw zero sump temperature increase when going from 5W-20 to 5W-30. Maybe it was a few tenths of a degree which I couldn't detect, lol.
Lets hypothetically say that 0W30 oil runs 5F hotter than 0W20 does in the same engine.
That is a good thing, because it would mean that the 0W30 oil is carrying away more heat from hot parts.
A very important part of what oil does, is help cool parts down!
That is a good thing, because it would mean that the 0W30 oil is carrying away more heat from hot parts.
A very important part of what oil does, is help cool parts down!
And then it transfers that heat to the cooling system increasing the coolant temp and allowing the parts to get hotter
And then it transfers that heat to the cooling system increasing the coolant temp and allowing the parts to get hotter
If your cooling system is fine, it should cool well enough that the coolant temp exiting the radiator and oil cooler if it has one, are barely warmer than they would have been, even if the oil wasn't cooling so good.
So in the end the parts are still running cooler.
Running too cold is also bad.
In winter I partially block off the radiator and oil cooler of all my vehicles, including semi trucks.
Last fall we got a sudden cold snap, and i had not yet blocked off the radiator some on my Accord.
After driving about 35 kms, I had to stop for the first red light of that day, and my cars idle wouldn't drop down under 1100 rpm because it still hadn't warned up enough.
A vehicle with a properly maintained cooling system should never over heat driving around town, or on the Hwy, even on a hot day.
If it does, something is wrong.
Having driven well over 8 million kms in my lifetime, never have I had an engine that was running too hot.
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