Oil/coolant temps on morning commute

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I have a "Carly adapter" for my BMW which, among many other things, allows me to monitor engine parameters. I was curious what my oil and coolant temps do on an average morning commute.

Vehicle is a second gen BMW X5 with the 4.8L V8 (9 quart sump + 1-2 quarts in the oil cooler). Oil is Castrol 0W-40 with about 2k miles on it.

Ambient temp throughout the whole trip: 45 F

7:55am - Start car. Oil and coolant at 45 F. Let idle for 5 minutes while I go inside and grab breakfast and coffee (my standard routine).
8:00am - Oil is at 81 F and coolant is at 132 F. Start driving to work (mix of stop/go and low-speed cruising around 45mph)
8:09am - Coolant is finally up to temp (220 F). Oil is at 180 F
8:13am - Arrive at work. Oil is at 190 F

I'm actually surprised how fast the oil came up to temp (oil operating temp is 210 - 220... thermostatically controlled) given that its a 9 qt. sump. I'm sure the piston oil-squirters have something to do with it.

Does anyone else have a short commute and track oil/coolant temps? Cheers.
 
Every BMW I have seen runs around 220 F. The newer N63 engine (hot-V twin turbo) runs at 225 while cruising. All of these engines have electronic thermostats and/or water pumps and will drop temperature when getting on the throttle or climbing a hill.
 
My commute to work is 12 miles and I did track my Corvette's oil and coolant temps the other morning when it was 26F outside. The car started out in my garage, so the oil and coolant were about 70F to start. After 4 miles of driving (with 3 of those being on the highway at 70-75mph) the coolant temperature got up to 192, the oil temperature was 181. Just one mile later the oil temperature caught up and hit 192. In order to help it warm up a bit quicker, I used the paddle shifters and held it in a lower gear than it normally would in drive. If I left it in drive it would keep the rpms closer to 1300-1500. But I chose the gears which would keep it closer to 2000 rpm. The next day, with the same outside temp, I tried keeping it in drive, and it took at least 2 miles longer before I reached these same coolant and oil temps.

I am happy at how quickly the oil gets up to temperature in this car, as this is pretty much the coldest temperature I will drive it to work in (because of the summer tires) I will test it again in warmer weather to see the difference.

FWIW, I can drive for a long time on the highway and my oil and coolant temp will stay at 192F the entire time.

My Corvette's engine holds 7 quarts of oil, the dry sump Corvettes hold 10 quarts and take a bit longer than mine to warm up based on what others have told me.
 
My commute is 10 miles on surface streets or 12 miles if I take the highway for the second half.
I have oil temp up on my MFD, but it doesn't show anything below about 90F. I'd assume I could get coolant temps and the full range of oil temps on my phone using Torque, but I haven't tried it yet.
I rarely idle for any length of time unless it's quite cold or I decide to leave it on to melt after I move it while clearing the driveway after a big snowstorm, we are in a 2 car garage/3 car situation for now and it's easiest for me to park outside. It's not unusual for the oil temp to still be under 150F when I get to work during a cold snap, believe it was about 190F when I got to work today with the temps right around freezing. Normal operating oil temps on the highway in warmer weather are ~195-210F, highest I have seen was something like 232F on a hot day while driving through mountains with a high HTHS 5W30 (M1 5W30 ESP) in the sump.
 
This is all very interesting. The question is whether it's possible for the oil temperatures to get as high or much higher than the water temperature. The reason ask that is my water temp never gets varies from 210 F whether it's a hot day at 90 F or a cold day at -15 F. A lot of people think their oil temperature is sky high in the summer. I'm not so sure.
 
Originally Posted By: Snagglefoot
This is all very interesting. The question is whether it's possible for the oil temperatures to get as high or much higher than the water temperature. The reason ask that is my water temp never gets varies from 210 F whether it's a hot day at 90 F or a cold day at -15 F. A lot of people think their oil temperature is sky high in the summer. I'm not so sure.


I think it depends on a few things like sump capacity, does it have an oil cooler or piston oil squirters, proximity of pan to exhaust, etc. I’d say most commuter cars have high oil temps in the summer due to them having no oil cooler and small sumps.
 
What I have found with all of my Corvettes is that when you start driving them hard for long periods of time, the oil temperature will indeed climb higher than the coolant. For example, the coolant might run in the 200-210 range, but then the oil temp would be 220-230.
 
Originally Posted By: Snagglefoot
This is all very interesting. The question is whether it's possible for the oil temperatures to get as high or much higher than the water temperature. The reason ask that is my water temp never gets varies from 210 F whether it's a hot day at 90 F or a cold day at -15 F. A lot of people think their oil temperature is sky high in the summer. I'm not so sure.


Yep,
my L67 Caprice, I got the oil temperature to 135C (type K thermocouple down the dipstick hole) just by holding the gearbox in "2", and driving 10 minutes at 100km/h...in "D" on the same trip it was low-mid 90s.

Revs increase oil temperature, with load being a smaller player.

Road load was the same in either case, just the revs changed.

That's why your oil warms up quicker driving off gently (and holding it around 2-2,500RPM) than letting it idle.
 
Originally Posted By: Shannow
Revs increase oil temperature, with load being a smaller player.

Road load was the same in either case, just the revs changed.

That's why your oil warms up quicker driving off gently (and holding it around 2-2,500RPM) than letting it idle.


I would assume this is due to friction being converted to heat in the main and rod bearings, and to a lesser extent the cam bearings.
 
Yep, mains, rods, and piston skirts...

Here's a couple of charts (some would call nonsensical finger painting), but I think add to the discussion.

First two specifically warmup...

The frictional drag in bearing surfaces as an engine warms up.


The difference between speed and load in warming the oil.


And a couple that demonstrate my Caprice experience, and why racetracks heat oil.

Heat flows OUT OF bearing and into the block from bearings in a small engine at different engine speeds.

 
Originally Posted By: Snagglefoot
This is all very interesting. The question is whether it's possible for the oil temperatures to get as high or much higher than the water temperature. ....A lot of people think their oil temperature is sky high in the summer. I'm not so sure.


Alternatively....

My Cummins diesel oil temp is always higher than coolant temps (once up to operating temperature).

It has a HUGE liquid-to-liquid oil cooler built-in where the oil filter threads onto, and RIGHT WHERE the lower radiator hose enters the engine!
 
Engines with coolant-to-oil type of heat exchanger will also warm up the oil much quicker than engines without that type of oil cooler.
 
Originally Posted By: dave1251
My commute is able 5 miles the oil is close to operating temp after 8 minutes at 40MPH. 7 quart capacity 5W30.


What vehicle/engine?
 
Took the 12 mile route this morning, probably a mistake as the one big intersection I need to get through to get to the highway was crazy busy before 7am and it took me two long light cycles to get through it.
Car sat outside overnight and it was right at freezing when I started it, left without idling and the oil temp was still below 90F after about 3 miles of easy surface street driving. Ended up going well over 90mph to avoid merging with two semis that were really booking when I got on the highway, but then unusually thick traffic took me down below 60mph right after that. I wonder if people were heading into work early today so they could leave early for the 3 day weekend (Good Friday-Easter)?
Oil temp was 187F when I pulled into the parking lot at work, after our discussion about turbo cooling yesterday I let the car idle while I put stuff away and tied my shoes. When I am in a hurry to beat traffic and the school buses on my street I will walk out to the car with my shoes loose and tie them at work to save 20 seconds or whatever...yeah, kind of weird.
 
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