Updated Thermal Control Valve

[trailblazer]

If you tow I’d still consider adding an additional cooling element. For my ‘09 Tahoe I added a Tru-Cool Max external element with a cold-weather bypass valve. Obviously you wouldn’t need said valve. This kept temps way down when pulling my 5500lb travel trailer. This kit was $105 shipped so shop around for similar models.

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[akbrener]

So, After all this I'm thinking I'm just going to tap and plug the thermostat housing instead of flipping the pill or trying to adapt the new style thermostat to my 2015. I live in Florida and it never gets below 40 where I am and is generally 80-95 degrees out 9months out of the year. I'm assuming I'll be just fine bypassing the thermostat completely. Thoughts? any better option for us 2015 owners?

You should be fine bypassing it. Heat kills transmissions.. the 6 speed has alot going on inside.. lots of clutches to build heat. Again, these things didnt have anything fancy until 2015 so let it flow to the cooler all the time.

 

[Doubeleive]

So, After all this I'm thinking I'm just going to tap and plug the thermostat housing instead of flipping the pill or trying to adapt the new style thermostat to my 2015. I live in Florida and it never gets below 40 where I am and is generally 80-95 degrees out 9months out of the year. I'm assuming I'll be just fine bypassing the thermostat completely. Thoughts? any better option for us 2015 owners?

I tapped mine and added extra cooling, no issue's my 2012 Denali did not even have a trans thermostat and I added the extra cooling to it as well
I drive my vehicles like they are on a race track so every little bit helps, we just took the truck out to eat and it's about 50 deg out, driving around 85mph the trans is at 122, if i had put my foot in it and ran it at 120-130mph it probably wouldn't have gone over 145 I watch it all the time.

 

[tom3]

Might take a look at this controller as an option:

https://gmauthority.com/blog/2022/02/improved-racing-launches-gm-automatic-transmission-cooler-adapter/

 

[Rygrego]

$200 seems a little high when the new GM thermostat does the same thing for $50

 

[Denali Brad]

Can anyone confirm that the TBV 86774933 will work on the 8L90 in a 2016? I appear I currently have the higher temp P/N 13511137.

Thanks in advance

 

[Denali Brad]

Can anyone confirm that the TBV 86774933 will work on the 8L90 in a 2016? I appear I currently have the higher temp P/N 13511137.

Thanks in advance

Thought I would increase our knowledge base by closing this out. I did purchase the 86774933 for my truck. Mounts to the transmission fine, but body of the unit has a slightly different angle where the lines mate with the unit, and it did not want to seal properly. My solution was to swap the new thermostat into the old housing.

 

[Prospect62]

Thought I would increase our knowledge base by closing this out. I did purchase the 86774933 for my truck. Mounts to the transmission fine, but body of the unit has a slightly different angle where the lines mate with the unit, and it did not want to seal properly. My solution was to swap the new thermostat into the old housing.

Excellent tip. I just got my new updated valve yesterday, was looking forward to a simple plug & play swap - guess it won't be that easy. It's never easy is it...

 

[tom3]

I also see there are two part numbers for this valve according to the line type.

86774933
(steel lines)

85563685
(aluminum lines),

 

[Prospect62]

I also see there are two part numbers for this valve according to the line type.

86774933
(steel lines)

85563685
(aluminum lines),

Oh that's interesting. Perhaps if this one doesn't fit right I'll try the one for aluminum lines (which I think is what I have anyway).

I was thinking, @Denali Brad may have had an issue because he has an 8L90 not the 6L80.

Great info, thank you!