Is this too much of a trans cooler? 4L60e, Tru-Cool 40k in Winter

[redhat]

I have had a Tru-Cool 40k transmission cooler sitting on the shelf for a year now. I initially wanted to install it on my Tahoe but at the time got concerned about not having enough heat in the unit during winter months. My factory transmission cooling arrangement is Trans -> radiator -> external factoryauxiliary cooler -> back to trans.

For reference, here in Western New York (Buffalo) it is on average 25-30 degrees for a few months of the year during December to February. But then again temps do fluctuate a lot. We have also had 2-3 week long spells on -5 through -15 degrees in years past. To sum it all up, we do get some pretty cold temps on occasion.

With that said, am I correct in thinking that simply removing the factory auxiliary cooler and substituting in the Tru-Cool (still run fluid through the radiator) would still provide enough heat in the trans for OK shifts and performance? Thoughts?

Below is a pic for size comparison.

 

[wag123]

Install a thermal bypass valve and you don't have to worry about it. This device will allow your transmission fluid to reach proper operating temperature before it opens and sends fluid through the auxiliary cooler. Tru-Cool makes one for the 40K.

Amazon.com

 

[Brian123]

I have had a Tru-Cool 40k transmission cooler sitting on the shelf for a year now. I initially wanted to install it on my Tahoe but at the time got concerned about not having enough heat in the unit during winter months. My factory transmission cooling arrangement is Trans -> radiator -> external factoryauxiliary cooler -> back to trans.

For reference, here in Western New York (Buffalo) it is on average 25-30 degrees for a few months of the year during December to February. But then again temps do fluctuate a lot. We have also had 2-3 week long spells on -5 through -15 degrees in years past. To sum it all up, we do get some pretty cold temps on occasion.

With that said, am I correct in thinking that simply removing the factory auxiliary cooler and substituting in the Tru-Cool (still run fluid through the radiator) would still provide enough heat in the trans for OK shifts and performance? Thoughts?

Below is a pic for size comparison.

View attachment 222957

You can call Tru-Cool and ask them if this Cooler has a Bypass in it. How this works is when the trans fluid is thick or cool, the fluid bypasses the Cooler. When the Fluid gets thin and Hot the Trans Fluid goes through the Cooler.

 

[4WD]

Doesn’t the TruCool LPD design with wider passages at the inlet so that cold ATF flows there - then as it thins - the fluid will move into the whole cooler (part of low pressure drop tech)

 

[4WD]

You can call Tru-Cool and ask them if this Cooler has a Bypass in it. How this works is when the trans fluid is thick or cool, the fluid bypasses the Cooler. When the Fluid gets thin and Hot the Trans Fluid goes through the Cooler.

I think it’s just variable passage TFA …

 

[redhat]

Doesn’t the TruCool LPD design with wider passages at the inlet so that cold ATF flows there - then as it thins - the fluid will move into the whole cooler (part of low pressure drop tech)

Yes it does, they claim that. Which is where my confusion lies. Is that enough? The OE cooler doesn't have any bypass or LPD, so in essence this would mimic the OE cooler.

I guess what I'm curious on is, would this cooler keep the trans too cold ever?

 

[edyvw]

Yes it does, they claim that. Which is where my confusion lies. Is that enough? The OE cooler doesn't have any bypass or LPD, so in essence this would mimic the OE cooler.

I guess what I'm curious on is, would this cooler keep the trans too cold ever?

Is there actual thermostat available for such set up?

 

[4WD]

I have only run air coolers post fluid/fluid - not sure how they work otherwise …

 

[4WD]

Yes it does, they claim that. Which is where my confusion lies. Is that enough? The OE cooler doesn't have any bypass or LPD, so in essence this would mimic the OE cooler.

I guess what I'm curious on is, would this cooler keep the trans too cold ever?

Not sure what year they started the thermostat - but we elected to gut one bcs it failed and overheated the transmission …
Think Clinebarger has commented on this …

 

[jetman]

@redhat
Install the bypass and mount it down low in the lower grill. This is talked about this a lot on the Tahoe/Yukon/Escalade forum.

 

[BrendanC]

i have a 40K on my 80e. i have bypassed the radiator cooler as that is how the transmission is “heated” from factory. there is no need for a thermostat if you drive it gently until
up to temp if the radiator is bypassed.

 

[SaberOne]

Looks good to me. If I ever get around to upgrading mine, I would put one in front of my LS3 and 6L80 that’s even larger.

 

[dumkid]

on my Mitsubishi the transmission fluid runs through external cooler first, then the radiator tank cooler. so if the external cooler works too good the radiator will reheat the fluid I think. and my transmission wont lock the torque converter until it's warm

plenty of Australians have 2-3 transmission coolers and/or bypass the radiator tank cooler and have no issues, but it's not too cold in Australia

maybe Molacule or Clinebarger know how cold is too cold for an automatic transmission