External engine oil cooler options?

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Charlie207

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I have the K5L HD cooling option for my Yukon, but I'm searching for ways to add more oil cooling.
What are my options? I'm searching for external engine oil coolers in between lulls at work, but am interested what you guys have already tried.

After replacing my radiator with a larger Champion radiator, and test driving it by going on a 120 mile drive in 90+ degree heat on mostly 75mph interstates. There were no leaks, and coolant temps seemed to be A-OK, so no worries there, but via Torque, my oil temps seemed to be very high ~230 degrees at it's peak while on the interstate.

I'm not aware if there is a direct way that the ECU measures the oil temp, but rather it provides an estimated temp. based on values provided from other sensors (oil pressure, coolant temp, RPM, etc.... correct me if I'm wrong).

Either way, 230 degrees sounds way too high.
 

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I have the K5L HD cooling option for my Yukon, but I'm searching for ways to add more oil cooling.
What are my options? I'm searching for external engine oil coolers in between lulls at work, but am interested what you guys have already tried.

After replacing my radiator with a larger Champion radiator, and test driving it by going on a 120 mile drive in 90+ degree heat on mostly 75mph interstates. There were no leaks, and coolant temps seemed to be A-OK, so no worries there, but via Torque, my oil temps seemed to be very high ~230 degrees at it's peak while on the interstate.

I'm not aware if there is a direct way that the ECU measures the oil temp, but rather it provides an estimated temp. based on values provided from other sensors (oil pressure, coolant temp, RPM, etc.... correct me if I'm wrong).

Either way, 230 degrees sounds way too high.
Aircraft piston engine oil gets a lot hotter than that. I'm of the opinion than the only external oil cooler needed on these is the one in the radiator tank - and many of these trucks don't even have that. Some sources I've read say that you want at least 220ºF to boil off the water and contaminants in the oil. My BMW diesel had an oil temp gauge instead of a coolant temp gauge for that purpose. The gauge range was 140-360ºF and normal oil temp was 240-250ºF on that engine, so 230ºF seems just fine to me.
 
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Charlie207

Charlie207

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Aircraft piston engine oil gets a lot hotter than that. I'm of the opinion than the only external oil cooler needed on these is the one in the radiator tank - and many of these trucks don't even have that. Some sources I've read say that you want at least 220ºF to boil off the water and contaminants in the oil. My BMW diesel had an oil temp gauge instead of a coolant temp gauge for that purpose. The gauge range was 140-360ºF and normal oil temp was 240-250ºF on that engine, so 230ºF seems just fine to me.

You know, I should have really done some research on oil temps - optimal vs. max. vs. dangerous - before posting. What is the normal temp. range for a 5.3 LS?
 
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Charlie207

Charlie207

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Found this from a 2013 Motor Trend article: https://www.motortrend.com/how-to/engine-oil-temperature/

For a dual-purpose car, engine oil needs to be at least 220 degrees F to burn off all the deposits and accumulated water vapor. For every pound of fuel burned in an engine, the combustion process also generates a pound of water! If engine sump temperatures rarely exceed 212 degrees (water's boiling point), the water will mix with sulfur (another combustion by-product) and create acids that can eventually damage bearings.


As for ultimate power potential, the general consensus among most racers is that hot oil and cool water make more power in most engines. Cold engine oil causes excessive frictional drag on the bearings and cylinder walls. A quality conventional motor oil will tolerate oil sump temperatures of up to 250 degrees, but starts breaking down over 275 degrees. The traditional approach is to try to hold oil temperatures between 230 and 260 degrees. Even on a short-duration, drag-only combo where oil is frequently changed, I would not want to routinely see under-200-degree oil temps.

A full-synthetic oil will withstand sump temperatures in excess of 300 degrees, and for hard-core professional racing, some oval-track race teams are experimenting with ultra-thin, specially formulated, race-only synthetics operating at 350 degrees or even higher.

Also remember that a high-end engine is built as a total combination. Piston-to-wall clearances, piston ring end-gaps, and bearing clearances are specifically tailored to match the engine oil's characteristics and intended operating temperature.
 

Foggy

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It's just a "calculated value" SO don't put too much credence into it...
Oil on a warm day will run 200*-250*....
IF you don't have an engine oil cooler in your radiator already, you could buy the
lines and adapter to fit it to the correct radiator.
230* is pretty normal on a summer day in these rigs (IF that's even the actual temp)
 

swathdiver

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A fella who goes by the screen name "Grumpy Bear" over at the GM-Trucks forum has been documenting this for years. He has a thread on his truck "Pepper" where he talks about this and how to combat it and measure performance.

The hotter the oil, the worse it is on the bearings and oil life is degraded. Get the coolant temp down, the oil temp will come down. You don't have to get above 212 to get rid of any water in the crank case, it will evaporate, more slowly.
 
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Charlie207

Charlie207

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It's just a "calculated value" SO don't put too much credence into it...
Oil on a warm day will run 200*-250*....
IF you don't have an engine oil cooler in your radiator already, you could buy the
lines and adapter to fit it to the correct radiator.
230* is pretty normal on a summer day in these rigs (IF that's even the actual temp)

Yeah, I have the K5L package. Thanks for validating the 230* temp. It makes total sense that the oil needs to be that hot to boil out any moisture.
 
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Charlie207

Charlie207

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A fella who goes by the screen name "Grumpy Bear" over at the GM-Trucks forum has been documenting this for years. He has a thread on his truck "Pepper" where he talks about this and how to combat it and measure performance.

The hotter the oil, the worse it is on the bearings and oil life is degraded. Get the coolant temp down, the oil temp will come down. You don't have to get above 212 to get rid of any water in the crank case, it will evaporate, more slowly.

Oh... well, disregard my last comment.

Will the addition of my oil catch-can help with that also? Or, is that more geared towards cold-weather starts?
 

Geotrash

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A catch can will remove a tiny amount of moisture but it's negligible compared to the regular PCV system. Catch cans are mainly about keeping oil out of the intake.

Sorry for the tangent here but I also can't help but wonder if GM's switch to 0W-20 oil on these engines in the later years for fuel economy might have something to do with some of the lifter failures we're seeing on them.
 

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