Oil temperature

OVERKILL

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Do you track it?
@YogiTheCat and I recently had a nice exchange about oil temperature, as it is one of his concerns in choosing an appropriate viscosity. He asked me at the time what my oil temp was when towing and I told him I hadn't really checked, but I expected it was pretty close to normal, given my wife's truck has a pretty substantial oil cooler.

Today I towed the Supra back from the cottage so it was a good time to monitor that. It didn't go above 106C (223F) the entire trip, despite a few WOT runs, some bumper-to-bumper due to an accident...etc.

In tracking the Jeep for the last week, which also has a rather massive heat exchanger, it sits at 106C too, so I'm guessing that's the temp FCA targets.

His truck doesn't have an oil cooler, so he sees a rather broad range of oil temperatures. Given how many trucks "back in the day" didn't have oil coolers either (my old F-250 sure didn't) I'm guessing this is only becoming a worry now as thinner oils, like 5w-20 and 0w-20, probably soon 0w-16 are spec'd for these applications. Viscosity control through temperature then becomes a potential concern.


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I watch it on my 135i pretty close, and it’s more or less right at the 240 mark (IIRC) all the time. It does vary slightly with ambient conditions.

Id agree that when temps go that high, viscosity comtrol is a concern. If it doesn’t deviate much above 100C, which I’d assume to be the design point, not a lot necessarily needs to be done.
 
@OVERKILL I definitely wouldn't run 5W-20 in a HEMI without an oil cooler. We took down the 13 speed Eaton transmission to do a rebuild and on my way to Concord I saw 230F and it's mostly flat. The transmission and trailer can't be more than 2000 LBS. I don't have an oil cooler. When towing heavier loads the temperature goes up to 240F, even 250F. So FCA might be targeting 106C, which is ~222F, however, they never thought about towing applications for trucks than don't have an oil cooler like mine. I opted to run a thicker oil and throw some Lubegard Bio/Tech in there. The motor purrs like a kitten on that combo. Still, I wish it had an oil cooler.
 
I do. The 300 very rarely exceeded 185F on the oil, the Ram likes to sit around 210F. The Ram definitely comes up to temp quicker than the 300 ever did.
 
I do. The 300 very rarely exceeded 185F on the oil, the Ram likes to sit around 210F. The Ram definitely comes up to temp quicker than the 300 ever did.

I guarantee that you have an oil cooler in that RAM 1500. FCA started installing them in all RAM model year 2018 and newer. The irony with mine is that it has a towing package... Well, I do have a trailer brake controller :cautious:
 
Yes. I watch mine all the time in my Sportwagen. Highest I've seen is 226 with high ambient and high sustained speeds; it varies between 210 and 221 more typically.
 
I guarantee that you have an oil cooler in that RAM 1500. FCA started installing them in all RAM model year 2018 and newer. The irony with mine is that it has a towing package... Well, I do have a trailer brake controller :cautious:
I do, you can see the coolant lines branching off to it. The Pentastar also has an oil cooler, part of the oil filter assembly. That trucks engine bay is the weirdest combination of “wow I can see the ground and reach that part!” and “how in the WORLD am I getting my hand back there, let alone a tool?!”
 
Do you track it?

Track? no- but do always monitor very close but not so much for the oil

In general, any temp below ~250F is a top threshold for most oils with the understanding that cooler is always better on the fluid and usually the machine. ( lot of variance there depending on the specific machine and oil recipe but that's arguing "kibbles and bits")

Heat is always a byproduct of work ( regardless of whether you are in tolerance or out of it) and needs to be removed ( usually the more the better)

On my keepers, I cool everything as much as is reasonable and add whenever realistically a value add.

That "heat" is a failure mechanism and/or enabler of both failure or degradation of almost every part and component of the engine and drive chain so monitoring heat is very important for anything one wants to keep indefinitely with a lower MTBF and TCO over the life.

Is that a guarantee of no failures? No, not even a sincere promise because things are going to fail but it does help in the long and short run
 
The oil temperature in both of our Pentastars runs about 185F in the summer and 165F or below in the winter. The highest temp I've ever seen is about 225F descending from the Eisenhower tunnel in Colorado using the engine as a brake. The RPMs were about 4000 for a few minutes, although there was no combustion heat, there was a LOT of friction. Amazing that friction alone can reject that much heat.

I cover most of the grill on my Durango in the winter to reduce the air across the radiator, in an attempt to get the oil temp above 165F. Below 165F the oil pump is always on the high pressure side and above it's on the low pressure side. I see no need to run around constantly with 90 pounds of oil pressure. The Charger must have considerably less airflow through the radiator and/or smaller radiator, because it has no trouble keeping the oil temp above 165F in the winter.
 
When BMW was having issues with their oil temps in the N52/54 before the oil cooler install update, they said 275 was max operating temp, and 300 was where the trouble started, so Ive always used that as a guide. My M cars never go above 210-220, my old A4 showed 205-210 constantly no matter what temps with syn. When they ran conventional it was about 240. I normally see about 225 in most of the BMWs we work on.
 
Do you track it?
@YogiTheCat and I recently had a nice exchange about oil temperature, as it is one of his concerns in choosing an appropriate viscosity. He asked me at the time what my oil temp was when towing and I told him I hadn't really checked, but I expected it was pretty close to normal, given my wife's truck has a pretty substantial oil cooler.

Today I towed the Supra back from the cottage so it was a good time to monitor that. It didn't go above 106C (223F) the entire trip, despite a few WOT runs, some bumper-to-bumper due to an accident...etc.

In tracking the Jeep for the last week, which also has a rather massive heat exchanger, it sits at 106C too, so I'm guessing that's the temp FCA targets.

His truck doesn't have an oil cooler, so he sees a rather broad range of oil temperatures. Given how many trucks "back in the day" didn't have oil coolers either (my old F-250 sure didn't) I'm guessing this is only becoming a worry now as thinner oils, like 5w-20 and 0w-20, probably soon 0w-16 are spec'd for these applications. Viscosity control through temperature then becomes a potential concern.


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Nothing I have gets over 100c, all have coolers of one type or another.
 
Nothing I have gets over 100c, all have coolers of one type or another.

Ironically our Hyundais have oil cooler while our RAM 1500 doesn't. Even the measly 2.4 GDI engine has one, right above the oil filter, and two giant coolant lines.
 
Ironically our Hyundais have oil cooler while our RAM 1500 doesn't. Even the measly 2.4 GDI engine has one, right above the oil filter, and two giant coolant lines.

That style is pretty common and works well, it also warms the oil faster in cold months. My VW uses that style, oil reaches temp quickly and maintains an even oil temp all year.
 
That style is pretty common and works well, it also warms the oil faster in cold months. My VW uses that style, oil reaches temp quickly and maintains an even oil temp all year.
Yep, that's the same style as on both the Jeep and RAM. I think the Jeep one is larger though.
 
Under normal driving, my RAM stays between 219-222F.

During a recent drive between Scottsdale and Sedona on I-17, oil temps regularly reached 235-240F on the uphill sections. I did experience some oil consumption on this trip, but I don’t think it was directly related to the high oil temps.
 
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