Upgrade OEM Transmission Cooler

[14SWTahoe]

That kit is only for the nbs right?

NBS and NNBS.

 

[14SWTahoe]

The OEM gauge seems to be very inaccurate. It was reading 170 to 180 on my drive home so when i got home i used my laser thermometer all around the transmission housing and didnt get a reading over 165. The readings on the transmission cooler were 20 degrees cooler than the tranny.

 

[TheAutumnWind]

The OEM gauge seems to be very inaccurate. It was reading 170 to 180 on my drive home so when i got home i used my laser thermometer all around the transmission housing and didnt get a reading over 165. The readings on the transmission cooler were 20 degrees cooler than the tranny.

The sensor is likely in the pan? Heat will radiate off of the external portion of the transmission. The temperature that we are interested in is the temp of the fluid itself. Of course the cooler will read as a cooler temp.

 

[14SWTahoe]

The sensor is likely in the pan? Heat will radiate off of the external portion of the transmission. The temperature that we are interested in is the temp of the fluid itself. Of course the cooler will read as a cooler temp.

Pan temp read about 40 degrees cooler than housing, so im not sure where the temp sending unit is. But def not in the pan.

 

[TheAutumnWind]

Pan temp read about 40 degrees cooler than housing, so im not sure where the temp sending unit is. But def not in the pan.

Interesting.

 

[14SWTahoe]

A bit more detail since I have more time to type it all out.

Transmission pan temp~105
Transmission housing @transfer case~145
Transmission housing @middle~145
Transmission housing @bell housing~165
Bell housing~205
Transmission cooler~145

I am wondering if the OEM gauge is measuring when the fluid comes out of the torque converter?

At that point I dont really care that the fluid gets 180 for a short period of time, it isnt enough to damage the fluid. The fluid running through the transmission is much cooler and the tranny itself isnt peaking at the gauge temp.

My last step will be to install one of these:

http://www.yourcovers.com/transpan_11025.php

One test listed on the website shows a temp drop of ~20F. Between that and the upgraded tranny cooler, if it isnt enough, nothing will be.

Anyone know where the temp sending unit for the transmission temp is?

 

[TheAutumnWind]

A bit more detail since I have more time to type it all out.

Transmission pan temp~105
Transmission housing @drive shaft~145
Transmission housing @middle~145
Transmission housing @bell housing~165
Bell housing~205
Transmission cooler~145

I am wondering if the OEM gauge is measuring when the fluid comes out of the torque converter?

At that point I dont really care that the fluid gets 180 for a short period of time, it isnt enough to damage the fluid. The fluid running through the transmission is much cooler and the tranny itself isnt peaking at the gauge temp.

My last step will be to install one of these:

http://www.yourcovers.com/transpan_11025.php

One test listed on the website shows a temp drop of ~20F. Between that and the upgraded tranny cooler, if it isnt enough, nothing will be.

Anyone know where the temp sending unit for the transmission temp is?

I wonder if there is more than one and it is giving you an average number?

 

[14SWTahoe]

I wonder if there is more than one and it is giving you an average number?

I dont know, but I did some more digging and found this thread...

http://www.silveradosierra.com/transmission/2014-6l80e-temperature-control-unit-t319770.html

If my Tahoe has one, this would explain a lot. Seems in 2014 they started installing a thermal bypass for at least the GMC yukon and some silverado's for the transmission fluid.

I checked the parts break down for my vehicle and year and it says I do not have one.

It would be bypassing the HD cooler until the temp gets above 180F. Going to check tonight when I get home as I didnt drive my truck today.

 

[TheAutumnWind]

I dont know, but I did some more digging and found this thread...

http://www.silveradosierra.com/transmission/2014-6l80e-temperature-control-unit-t319770.html

If my Tahoe has one, this would explain a lot. Seems in 2014 they started installing a thermal bypass for at least the GMC yukon and some silverado's for the transmission fluid.

I checked the parts break down for my vehicle and year and it says I do not have one.

It would be bypassing the HD cooler until the temp gets above 180F. Going to check tonight when I get home as I didnt drive my truck today.

Seems odd that it would bypass the cooler until 180*. I could see 125* or something.

 

[14SWTahoe]

No bypass in mine...

I will install upgraded trans pan and see how much that helps. I trust the measurements I took with my laser thermometer, the trans is staying cool but the fluid is spiking somewhere (TC most likely).

Between upgraded pan and aux cooler, its going to be what its going to be, not going to throw more money at it.

There is no signs of an external temp sending unit on the trans case, so it must be internal to the trans where it measures the fluid temp. Maybe there is an internal bypass in the trans as well?? Who knows.

Just gonna start towing and see what the temp is.