High oil temps

Floridians favorite vacation fantasy?... “I’m gone skying in Colorado, baby”...Flatness to madness!


Let’s go back to high oil temps.
 
Floridians favorite vacation fantasy?... “I’m gone skying in Colorado, baby”...Flatness to madness!


Let’s go back to high oil temps.

I think in OP's case, there was airflow and pretty normal operation as cars do go up steep grades and even long windy twisty roads like US-30 in Western PA etc from time to time. I am curious how high they get with extended idling and slow moving traffic. I would say stop and go but that is like a combination of the previous two.
 
Look up internal engine temps - pistons can see 600F, conrods 475 at the top and 300 at the crank... oil is getting up in all that. There’s a lot more going on in there than we realize. You haven’t hurt your oil at all. Run it and enjoy.
 
Look up internal engine temps - pistons can see 600F, conrods 475 at the top and 300 at the crank... oil is getting up in all that. There’s a lot more going on in there than we realize. You haven’t hurt your oil at all. Run it and enjoy.
Yes but that”s why sumps contain 5,6,7,8 quarts to help bring the temp back down. Take the Chevy LS engine in the 2020 Silverado. It specs 0w20, and has an 8 quart system. The pickup screen takes the oil where it is sucked up to the oil pump, through the oil filter, up as high as the heads where some of the oil covers the rockers, some goes to the cam and some goes down to the crank and rod bearings, and THEN some of it is exposed to the piston and combustion chamber walls. The bulk of the oil is at just over 212 degrees F normally. The oil passes across the hot journals and cylinder in micro seconds and falls back in the pan. Also if the engine is equipped with an oil cooler in the rad, it will help keep the temp as close as possible 212 F. At high rpms like with track use or high turbo temps experienced while going up mountains, the temp rises and the viscosity drops significantly. If you do this a lot and believe a higher viscosity decreases wear, then you might want to go up a grade ( don’t mind the pun). I routinely drive a road that climbs 2500 ft in 20 miles. If I had a turbo, it would be working. :)
 
Oiling system of a Chevy LS engine.

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Here is a graph of some sample oils. You can see the effect of temperature on viscosity. You can decide what viscosity you want to see when you drive up that mountain under full load with the Turbo working hard.

1599102198644.png
 
Thank you for your responses.
Usually I make this trip 2 -3 times a year. I changed the oil just before the trip because the car was due for an oil change and service so I wasn't feeling comfortable doing the trip with the old oil. Next week I am going to change the oil again and all the filters. I have already bought the oil: Mobil1 esp 5w30. Maybe is a waste to change the oil so soon (1.5k.miles) but since I haven't changed the oil filter I am going to change it again. I will run the new oil for another 5k and after that I will try something thicker. As I said am thinking about trying Ravennol RUP 5w40 (229.51).
Density at 20°Ckg/m³846,0DIN 51757
Colouryellow brownvisual
Viscosity at 100°Cmm²/s14,3DIN 51562
Viscosity at 40°Cmm²/s87,5DIN 51562
Viscosity index VI169DIN ISO 2909
HTHS at 150°CmPа*s3,9ASTM D5481
CCS Viscosity at -30°CmPa*s4510ASTM D5293
Low Temp. Pumping viscosity (MRV)mPa*s21.300ASTM D4684
Pourpoint°C-51DIN ISO 3016
Noack Volatility%6,0ASTM D5800/b
Flash point°C244DIN ISO 2592
TBNmg KOH/g8,3ASTM D2896
Sulphated ash0.8
 
Yes, you probably would be correct on that, it will be cooler, but not cooler than the water temp in the rad. Since Mercedes has given the OK essentially of using a xw40 oil I would recommend choosing one of them. If you use the search function in this forum, with your name and words “oil temperature” you will be able to see posts about other folks experience with oil temperature issues. Good luck. PS, I’ve been to Greece twice. Wonderful country and people.
Whoops. Search “oil temperature” but without your name. That will grab posts from others. 🙃 Good choice on the oil.
 
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Although that is approaching the high end of the safe range, I really dont think anything was harmed. I would switch to a 40 weight and see if anything changes.
 
Going up in viscosity will only make the oil heat up more though. But if the extra oil temp rise is minimal you can be assured of higher viscosity between all shearing surfaces
 
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