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

Tozan said:

In my experience it helps bring it up to temp faster and stops the error code form activating. When the error code is triggered the fan came on full time and ac would shutdown. I would have to go in and reset or restart the car to get things working again.

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Ok, so not something I should focus on when battling high temps. I have an aftermarket 2 core aluminum radiator, but from Amazon, not the Core brand or whatever it is that doesn't come with a restrictor. I never checked mine, but it gets up to temp normally and then I am battling higher temps.

Tozan said:

In my experience it helps bring it up to temp faster and stops the error code form activating. When the error code is triggered the fan came on full time and ac would shutdown. I would have to go in and reset or restart the car to get things working again.

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This is 100% correct.

Sangster said:

Ok, so not something I should focus on when battling high temps. I have an aftermarket 2 core aluminum radiator, but from Amazon, not the Core brand or whatever it is that doesn't come with a restrictor. I never checked mine, but it gets up to temp normally and then I am battling higher temps.

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Does your radiator have an oil cooler on it? in front of the radiator?

Tozan said:

Does your radiator have an oil cooler on it? in front of the radiator?

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Yes, Trucool 40k right smack dab in front of the AC condenser. Have to move it down below next. I'm assuming you are referring to the transmission fluid cooler....

Sangster said:

Yes, Trucool 40k right smack dab in front of the AC condenser. Have to move it down below next. I'm assuming you are referring to the transmission fluid cooler....

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That is most likely why it is running hotter. With the air having to pass through three layers it is reducing the air flow. I would either move the oil cooler to a new lower location or try to move it so there is a few inches between them allowing a little more air to move around them.

So did anyone just try to tune the fans? Ive seen a similar write up on the truck page with the same issues with a 6.2l sierra and just using hp tuners fixed his issue. Supposedly the fans run around 70% (+/-) duty on high and will kick up to 90% just before overheating. Im having the same issue on our 11 xl 6.2 denali, trans temp stays fine until the coolant temps reach 235.

I have looked into fan tuning w HPT.. On the trucks/suvs there is NO SPEED Override option
The fans turn OFF at about 45ish mph... really no matter what you do..
I don't have issues with it running hot until I'm pulling my large travel trailer
at about 55 mph. And that will tend to up my ECT into my "uncomfortable" zone
But at least now, I can turn on my independent trans cooler fan to help dissipate
some of that heat
I may try to send a "ticket" into HPT to see if they will add a channel to make
it possible to override the MPH / Fan Turn Off Speed with some sort of option
for ECT to override it. But I'm fairly new with the HPTuners - for now

Thethirdtwin After climbing a mostly 6% grade for 16 miles. I’ve been in the same location with thecopcar after upgrading the external cooler. It topped 200.

Sangster said:

I have an aftermarket 2 core aluminum radiator

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GMs engineers spent a lot of time and money getting our radiators right, if they wanted a second row, they would have added it. I have read in other professional publications that our cooling systems are not like those of thirty or forty years ago when a 4 row was an upgrade to a 2 or 3 row radiator. These new systems actually degrade with additional rows and we are seeing that all aluminum radiators are not all that either.

swathdiver said:

GMs engineers spent a lot of time and money getting our radiators right, if they wanted a second row, they would have added it. I have read in other professional publications that our cooling systems are not like those of thirty or forty years ago when a 4 row was an upgrade to a 2 or 3 row radiator. These new systems actually degrade with additional rows and we are seeing that all aluminum radiators are not all that either.

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But the fact that heat has been an issue for these trannys you don't think a cooler like a 40k which drops temps to 130ish is a benefit?