Oil Cooler Blocking Plate

[Geotrash]

I plan to do the oil cooler delete maybe in the spring when I do the next oil change. Get a simple plate online and then you never have to worry about the lines themselves leaking. It also isn't a cooler so much as it is a warmer to help the oil heat up so I don't think there will be any issues going forward.

It's definitely both. It's been studied by at least a few folks here: Take the radiator's heat exchangers out of the circuits, and fluid temps will peak significantly higher under sustained loads, like when pulling a camper up a mountain pass in the summer. I have demonstrated this with transmission fluid using different configurations of coolers. Peak fluid temperature was 30ºF higher (265ºF) at the top of a pass I pull our camper over several times a year, than it was with the radiator's heat exchanger in the circuit.

 

[Noggles]

It's definitely both. It's been studied by at least a few folks here: Take the radiator's heat exchangers out of the circuits, and fluid temps will peak significantly higher under sustained loads, like when pulling a camper up a mountain pass in the summer. I have demonstrated this with transmission fluid using different configurations of coolers. Peak fluid temperature was 30ºF higher (265ºF) at the top of a pass I pull our camper over several times a year, than it was with the radiator's heat exchanger in the circuit.

Was that not using an external cooler at all or an external but without going through the radiator as well?

 

[Geotrash]

Was that not using an external cooler at all or an external but without going through the radiator as well?

I was using a Derale 13960 fan-forced external fluid cooler that I had initially plumbed with the radiator's end tank heat exchanger out of the loop, which turned out to be the mistake. So I plumbed the radiator back into the loop and that's what brought the fluid temperature (at the top of the mountain) down again.

It's worth mentioning also that the GM Upfitters manual for these trucks specifies that fluid coolers should be plumbed in series with, and downstream from, the radiator's heat exchangers, if so equipped.

 

[j91z28d1]

yeah.. I don't think people realize these trucks don't have actual oil temp sensors. it's just a fake number you see.

oil Temps can get significantly higher than coolent Temps when working hard. 300deg sump Temps are not unheard of and the cooler is right off the pump, which when you compress a fluid it adds heat.
gm doesn't send the corvette into reduced power mode till 320deg oil Temps, which they can't hit pretty easily on a track lap with even a novice driver. towing some of these big campers up mountain passes is working these trucks harder than the 3k lbs car that only sees full throttle for a few seconds at most.


it absolutely cools the oil to run it thru the radiator end tank and usually more efficiently than air to oil doesn't. if you don't tow, sure you won't need it. my yukon doesn't have one but it was designed to be a minivan, not a tow rig.

your call if you need it or not.

 

[Foggy]

My corvette has an actual oil temp sensor & gauge readout.
I've seen it pretty dang high in high summer temps and that's
just normal driving (read old man on the highway)
I can't imagine what my temps would be on my Yukon towing
my camper or even just driving normal.. It's twice the weight of my car !!!
And the rpm ranges are about the same !!

 

[Noggles]

I was using a Derale 13960 fan-forced external fluid cooler that I had initially plumbed with the radiator's end tank heat exchanger out of the loop, which turned out to be the mistake. So I plumbed the radiator back into the loop and that's what brought the fluid temperature (at the top of the mountain) down again.

It's worth mentioning also that the GM Upfitters manual for these trucks specifies that fluid coolers should be plumbed in series with, and downstream from, the radiator's heat exchangers, if so equipped.

Very interesting. Do you think it was caused by the thinner air at altitude? I’ve read for a long time about deleting the stock in radiator cooler and going with a bigger external cooler (at least on the gmt800 trucks which uses the exact same radiator and trans cooler setups) causing massive trans fluid temp drops. I don’t understand why running your trans fluid through a heat sink that also contains 210-230 degree engine coolant would be better than it having its own divorced loop of cooling?

 

[donjetman]

I would never delete the radiator heat exchanger from the loop.

Engineers use heat exchangers for fluid temperature stability.

Lets say the oil or atf leaves the engine and/or tranny at 250+ degrees, then goes into the radiator thats at 210 degrees (or less because its been cooled already since its left the engine), thus being cooled somewhat.
Of course in the winter you want to heat the oil and/or atf so that its viscosity (resistance to flow) is correct.

 

[Geotrash]

Very interesting. Do you think it was caused by the thinner air at altitude?

I don't. It was in the Shenandoah Mountains on a road we take several times a year with our camper. Elevation at the top is less than 3500'.

I’ve read for a long time about deleting the stock in radiator cooler and going with a bigger external cooler (at least on the gmt800 trucks which uses the exact same radiator and trans cooler setups) causing massive trans fluid temp drops. I don’t understand why running your trans fluid through a heat sink that also contains 210-230 degree engine coolant would be better than it having its own divorced loop of cooling?

Don's answer is spot on. To explain a little further, oil-to-water heat exchangers are many times more thermally effective than oil-to-air exchangers are. So the heat exchanger in the radiator end tank can easily shave off 30-40ºF before it gets to the external oil-to-air cooler.

Here's a whole thread documenting my (and others') experiments with coolers:

Keeping coolant and transmission temps under control when towing in the summer heat

Hi All, the 2012 XL Denali is a towing beast, but after the cam upgrade, new HD torque converter, and adding the Tru-Cool 40K in front of the radiator, the engine itself is running warm now that we're getting into spring. Hauled our 6500 lb camper down to Virginia Beach this weekend in 83º...

www.tahoeyukonforum.com

Bon apetit!

TL/DR, a large external cooler like the Trucool 40K will block enough airflow to trigger engine cooling problems when towing uphill in the summer heat - especially on 6.2L rigs because they generate more power and heat. Lots of documented examples of this on these pages. Hence why I ended up with the fan-assisted Derale mounted below the bumper behind the lower grille on my 2012 XL Denali. It's proven to be the perfect setup for my needs.