Is this a crazy idea to cool my 4L60E transmission?

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davidavidd

davidavidd

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Thank you all for your good advice, forgot to mention that I have an external radiator too, I will do the experiment next week; if it doesn't work or I'm not convinced I'll just plug it in as it was.
 

latvius

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So you want to run trans oil lines into the radiator cooler, then to the other radiator cooler, then to the external cooler? Are you trying to make it a BMW?
Just by pass the radiator and run the lines to the external cooler.
Look at it this way you eliminate the chance of your radiator leaking into your transmission and tanking it. Your plan increases this chance by x2.
 

Geotrash

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So you want to run trans oil lines into the radiator cooler, then to the other radiator cooler, then to the external cooler? Are you trying to make it a BMW?
Just by pass the radiator and run the lines to the external cooler.
Look at it this way you eliminate the chance of your radiator leaking into your transmission and tanking it. Your plan increases this chance by x2.
I did this on my '12 XL Denali with a Derale 13960 and it didn't work out. The fluid-to-air cooling method is far less efficient than water-to-fluid so I was getting spikes to 265ºF towing our 7K lb camper over the Blue Ridge mountains. I plumbed the radiator end tank cooler back into the loop before the external cooler and problem solved. The radiator taks a big cut of the heat out of the fluid so that the external cooler can finish the job.

In my opinion, what the OP is trying to do is a mistake also and won't deliver the results he's looking for. The best cooler setup on these is the way the factory did it. After numerous experiments on my own and studiously logging data with various coolers and configurations, I gained nothing over the factory setup.

Lots of guys love the Trucool 40K but unless you're towing, or it's 100ºF in the summer, you'll never get the fluid to the minimum 150ºF that GM recommends. And if you have a 6.2L, the Trucool in front of the radiator will block enough airflow to cause engine cooling problems when towing.

I finally landed on the Derale 13960 mounted below the front bumper behind the lower grille on the Denali and plumed in series with the radiator's cooler. It's absolutely perfect. Warms nicely to 160ºF in daily driving with no trailer, and never gets above 230ºF towing over the steepest passes in the Blue Ridge or the Rockies. And the engine stays nice and cool, too.
 

latvius

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I did this on my '12 XL Denali with a Derale 13960 and it didn't work out. The fluid-to-air cooling method is far less efficient than water-to-fluid so I was getting spikes to 265ºF towing our 7K lb camper over the Blue Ridge mountains. I plumbed the radiator end tank cooler back into the loop before the external cooler and problem solved. The radiator taks a big cut of the heat out of the fluid so that the external cooler can finish the job.

In my opinion, what the OP is trying to do is a mistake also and won't deliver the results he's looking for. The best cooler setup on these is the way the factory did it. After numerous experiments on my own and studiously logging data with various coolers and configurations, I gained nothing over the factory setup.

Lots of guys love the Trucool 40K but unless you're towing, or it's 100ºF in the summer, you'll never get the fluid to the minimum 150ºF that GM recommends. And if you have a 6.2L, the Trucool in front of the radiator will block enough airflow to cause engine cooling problems when towing.

I finally landed on the Derale 13960 mounted below the front bumper behind the lower grille on the Denali and plumed in series with the radiator's cooler. It's absolutely perfect. Warms nicely to 160ºF in daily driving with no trailer, and never gets above 230ºF towing over the
steepest passes in the Blue Ridge or the Rockies. And the engine stays nice and cool, too.

If you live in cold weather get one of these - problem solved.
If fluid to water is more efficient why did my 2005 Denali have a fluid to air trans cooler? I upgraded the stock one to a tru cool model, it's bigger and my trans temps are cooler.




1712843128680.png
 

Geotrash

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If you live in cold weather get one of these - problem solved.
If fluid to water is more efficient why did my 2005 Denali have a fluid to air trans cooler? I upgraded the stock one to a tru cool model, it's bigger and my trans temps are cooler.




View attachment 425816
It's a good idea but I would want it to open at 150ºF, not 180. A similar valve is stock on the 2015+ rigs and they've had heat-related transmission problems as a result. The problem is that in really hot weather, either with a rig full of people and stuff, or when towing, you have less thermal headroom to work with and the fluid spends more time at higher temperatures than it would if you started cooling it at 30ºF lower temperature. 150ºF is the minimum that GM sets for both optimal fluid viscosity and to rid it of any residual moisture. But the warmer the fluid gets above that, the faster the additives break down and the harder it is on the soft parts (e.g. seals) in the transmission.
 

latvius

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OP writes
1712847536932.png
So why are you posting about what is needed for cold environments?

I won't even get into your thermal headroom theory or the that you never replied to my rebuttal of your radiator cooler cools better than external air cooler.
If you're going to quote what "GM says" you should include a reference, anyone can say "GM said" anything. Doesn't make it true.
 

Geotrash

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OP writes
View attachment 425824
So why are you posting about what is needed for cold environments?

I won't even get into your thermal headroom theory or the that you never replied to my rebuttal of your radiator cooler cools better than external air cooler.
If you're going to quote what "GM says" you should include a reference, anyone can say "GM said" anything. Doesn't make it true.
Who are you talking to?
 

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