What if "low tension ring" theory is all wrong?

[Faawrenchbndr]

That engine was not available in the US market for the HRV.
It was available here for the CRV, and no it does not have an oil cooler, or oil temp sensor.
Someone who owns one can look in the data list, to see if it displays an estimated oil temperature.

Well, I can tell you for sure 2024 Ford F150 has an oil cooler as well as an oil temperature sensor. Yes, an oil temperature sensor for the engine, not the transmission or the differential or the transfer case.

 

[4wd]

What is your answer to the question of what operating temperature is then?
Is it not possible to tell without an oil temperature gauge?
Would that temperature be the same on an engine with a non-temperature regulated oil cooler, as one without an oil cooler?

I don’t have anything without oil temp and coolers … but certainly have never seen oil temps 30°/40°F higher than coolant temps … more like 10° and only after around 20 minutes on the road …

 

[goblin]

...but certainly have never seen oil temps 30°/40°F higher than coolant temps …

Oil temps 30°/40°F higher than coolant temps are pretty much to the degree what I see when I switch my econosuv to manual shifting in dense traffic, with brief jolts to 5k rpm. 110°C vs 90°C.

Regular cruising equalizes them to within a few degrees, as the rpms remain very conservative in auto mode. Rarely need more than 3000rpm.
I never drove there, but I suspect being in a rush on San Francisco's hills will keep my oil temps at a stable 110°C.

I find this normal, I suspect oil temp staying under 212°F will fail to even evaporate any humidity and condensate in the oil.

 

[Faawrenchbndr]

I don’t have anything without oil temp and coolers … but certainly have never seen oil temps 30°/40°F higher than coolant temps … more like 10° and only after around 20 minutes on the road …

Get behind a smaller displacement turbo charged engine and you’ll see those oil temperature is higher than coolant temperatures. 30 to 40° in the summer while towing yeah that’s possible.

 

[edyvw]

This is absolutely true. Nissan VQ's have a donut on the filter that pulls coolant immediately on engine entry from the water pump - so bottom of rad coolant is like 160F even on hot day. Lots of test data in that world shows the oil temperature stays pretty low - even under harsh duty like long, slow climbs off road or Z car track days. What BMW does might be completely different. At minimum the size of the sump and its location will have some affect.


Toyota Dynamic Force which is likely one of the most common engines sold today has no oil cooler - except in a a few variants that have higher rated tow capacity - like Rav4 TRD/Adventure/Limited. Mine has no engine oil cooler.

Low oil temperature means there is an issue they are mitigating by running it low.




2023 RAV4 LE:

 

[SC Maintenance]

Low oil temperature means there is an issue they are mitigating by running it low.




2023 RAV4 LE:
View attachment 317797

Doubtful. Its only included on Rav4's with the extended tow rating, most have no engine oil cooler. The engine has a variable volume ECU controlled oil pump and runs 0W-16. The Dynamic Force 2.5 has proven to be extremely reliable - its likely Toyota's highest production engine and probably has been since at least 2019.

Not sure what they could be compensating for when they have no other problems.

 

[edyvw]

Doubtful. Its only included on Rav4's with the extended tow rating, most have no engine oil cooler. The engine has a variable volume ECU controlled oil pump and runs 0W-16. The Dynamic Force 2.5 has proven to be extremely reliable - its likely Toyota's highest production engine and probably has been since at least 2019.

Not sure what they could be compensating for when they have no other problems.

You can put your VIN and check under engine cooling.
That's not real oil cooler. It is heat exchanger. Its primary role is to speed up oil warming as coolant is warming up faster. It has its limits (big ones) when it comes to oil cooling.
I am not sure what heat exchanger or oil cooler has to do with issues.

 

[goblin]

... Its primary role is to speed up oil warming as coolant is warming up faster...

The best of both worlds in the transitional phases (cooling and warming) for both fluids...

Coolant warms faster than oil, then warms the oil.
Oill cools down slower than coolant, so once you stop the engine on a cold day - the oil remains warm long after the coolant got cold. And helps warm the coolant on restart once they start to circulate.

 

[Faawrenchbndr]

You can put your VIN and check under engine cooling.
That's not real oil cooler. It is heat exchanger. Its primary role is to speed up oil warming as coolant is warming up faster. It has its limits (big ones) when it comes to oil cooling.
I am not sure what heat exchanger or oil cooler has to do with issues.

A heat exchanger is a cooler

 

[SC Maintenance]

You can put your VIN and check under engine cooling.
That's not real oil cooler. It is heat exchanger. Its primary role is to speed up oil warming as coolant is warming up faster. It has its limits (big ones) when it comes to oil cooling.
I am not sure what heat exchanger or oil cooler has to do with issues.

I don't need to check my VIN - I can look at my engine.

Toyota calls it a cooler - but yes if the coolant is warmer than the oil it will technically warm the oil. However since its pulling from the radiator side of the water pump its most likely it will only warm briefly on cold start.

I am still not sure what your trying to infer from some supposed issue? I think your trying to jam the worlds round peg into BMW's square hole.

 

[edyvw]

A heat exchanger is a cooler

It is. But, it has limited effectiveness.

 

[edyvw]

I don't need to check my VIN - I can look at my engine.

Toyota calls it a cooler - but yes if the coolant is warmer than the oil it will technically warm the oil. However since its pulling from the radiator side of the water pump its most likely it will only warm briefly on cold start.

I am still not sure what your trying to infer from some supposed issue? I think your trying to jam the worlds round peg into BMW's square hole.

View attachment 317815

Ah so it has it.
“If the coolant is warmer?”
They can do that way to keep oil in check under light loads. It is chap way to do it.
Whether it is on radiator or engine side on RAV4 I don’t know. Generally not interested too much in microwaves.

 

[Mainia]

Ah so it has it.
“If the coolant is warmer?”
They can do that way to keep oil in check under light loads. It is chap way to do it.
Whether it is on radiator or engine side on RAV4 I don’t know. Generally not interested too much in microwaves.

For my wife's 2014 Rav4, they call "the hockey puck" a coolant "heater" or transmission "heater".. One of those, but definitely heater.

 

[edyvw]

For my wife's 2014 Rav4, they call "the hockey puck" a coolant heater or transmission heater.

Yeah. I have two on Sequoia. One on filter housing and one on transmission.
Tundra had real oil cooler on transmission until 2018. After 2018 it has puck which works “excellent “ while towing, if 260f is “excellent “ transmission temperature
I already got oil cooler lines and thermostat for Sequoia from pre 2018 Tundra. Puck is attached to thermostat, because primary role of puck is to warm up fluid.

 

[Mainia]

Yeah. I have two on Sequoia. One on filter housing and one on transmissionmission.
Tundra had real oil cooler on transmissionmission until 2018. After 2018 it has puck which works “excellent “ while towing, if 260f is “excellent “ transmissionmission temperature
I already got oil cooler lines and thermostat for Sequoia from pre 2018 Tundra. Puck is attached to thermostat, because primary role of puck is to warm up fluid.

Her Rav4 is set up for towing a super lite all aluminum pop up camper, I did add a 15 row transmission oil cooler before we towed with it. No way did I trust the little hockey puck to transmissionfer any heat away.

 

[SC Maintenance]

Ah so it has it.
“If the coolant is warmer?”
They can do that way to keep oil in check under light loads. It is chap way to do it.
Whether it is on radiator or engine side on RAV4 I don’t know. Generally not interested too much in microwaves.

Liquid to liquid cooler is much more efficient than liquid to air cooler. Something most people fail to understand. heat transfer capacity of air is pretty low compared to coolant.

The simple liquid / liquid transmission coolers inside most radiators works quite well for its size. A small radiator posing as a "cooler" likely cools much less. But it takes heat transfer expertise to understand this.

 

[edyvw]

Liquid to liquid cooler is much more efficient than liquid to air cooler. Something most people fail to understand. heat transfer capacity of air is pretty low compared to coolant.

The simple liquid / liquid transmission coolers inside most radiators works quite well for its size. A small radiator posing as a "cooler" likely cools much less. But it takes heat transfer expertise to understand this.

It is efficient if right size, which they are not. No puck like one on RAV4 will do what 11row air to liquid will do. Put right size, well yeah, you can keep always coolant temperature and oil temperature same, regardless of what you do.
How big is that liquid to liquid cooler inside radiator? 2nd generation Tundra had that. Simple liquid to liquid coolers use both air and liquid to cool off. Not just liquid. And they are pretty sizable. So not available on many vehicles.
Air to liquid radiator like Hyden 679/689 actually cools better than liquid to liquid Tundra had until 2018. Which is why they are popular upgrade.

 

[SC Maintenance]

It is efficient if right size, which they are not. No puck like one on RAV4 will do what 11row air to liquid will do. Put right size, well yeah, you can keep always coolant temperature and oil temperature same, regardless of what you do.
How big is that liquid to liquid cooler inside radiator? 2nd generation Tundra had that. Simple liquid to liquid coolers use both air and liquid to cool off. Not just liquid. And they are pretty sizable. So not available on many vehicles.
Air to liquid radiator like Hyden 679/689 actually cools better than liquid to liquid Tundra had until 2018. Which is why they are popular upgrade.

This is ATF cooler but same concept. Xterra comes with both a in radiator cooler (basically just a simple tube maybe 12 inches long) , and a Air cooler that is pretty close to the size of a Hayden 679. There actually installed in series in Xterra. An Engineer that goes by Jeff_RedX in the Xterra world tested with thermocouples in the cooler lines testing both the the liquid cooler and air cooler. I will summarize his conclusions although you might wish to read the whole test thread: https://www.thenewx.org/threads/atf-temperatures-and-cooling-system-performance.30287/

"There was no evidence of the rad-atf cooler heating the atf."

"The rad cooler is an effective heat exchanger at low speeds when heat generation in the transmission is high. "

 

[edyvw]

This is ATF cooler but same concept. Xterra comes with both a in radiator cooler (basically just a simple tube maybe 12 inches long) , and a Air cooler that is pretty close to the size of a Hayden 679. There actually installed in series in Xterra. An Engineer that goes by Jeff_RedX in the Xterra world tested with thermocouples in the cooler lines testing both the the liquid cooler and air cooler. I will summarize his conclusions although you might wish to read the whole test thread: https://www.thenewx.org/threads/atf-temperatures-and-cooling-system-performance.30287/

"There was no evidence of the rad-atf cooler heating the atf."

"The rad cooler is an effective heat exchanger at low speeds when heat generation in the transmission is high. "

That works if ATF warms up faster than coolant.
In engine, whichever fluid warms up faster (which is coolant) will warm up oil.
And that rad cooler might work in town. Towing and relying only on that (like Toyita did) won’t work. Or it will, until transmissionmission dies. Hence, upgrades.

 

[SC Maintenance]

That works if ATF warms up faster than coolant.
In engine, whichever fluid warms up faster (which is coolant) will warm up oil.
And that rad cooler might work in town. Towing and relying only on that (like Toyita did) won’t work. Or it will, until transmission dies. Hence, upgrades.

You keep changing the goalposts. Now were towing? What does that have to do with heat transfer in general?

What cooler has to do with it? Which one? Fluid to fluid “cooler,” which really serves to accelerate oil temperature raise, or real radiator oil cooler? Puck or heat exchanger is primarily accelerant.

So I just showed actual test data that this is untrue - that liquid / liquid coolers are not heaters. Same applies to liquid/liquid engine oil coolers.