Updated Thermal Control Valve

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GranPrix

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Drove around town twice today in 92 degree temps and hit 162 and 144. If that's the highest it gets I'm good otherwise I'll probably get a trucool.
 

Mr. 960

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As mentioned you can't take everything out. Doing this will trap air in the lines and the fluid will find the path of least resistance and flow right back into the trans bypassing the cooler. Also - you need to take note of where the half moon shape is on top of the cover. It is imperative that it goes back in the correct clocked position. It has passages in the body and if not put back properly it will impede or block flow to the cooler lines.
 

Sparksalot

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As mentioned you can't take everything out. Doing this will trap air in the lines and the fluid will find the path of least resistance and flow right back into the trans bypassing the cooler. Also - you need to take note of where the half moon shape is on top of the cover. It is imperative that it goes back in the correct clocked position. It has passages in the body and if not put back properly it will impede or block flow to the cooler lines.
I did not see any mention of the clocking in the videos I watched about it.
 

RLC2020

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A few things after having the pill flipped for a few months now. Temps are great, usually around 140 empty, up to 175 or so light towing. Much better than the near 200 it was at before. Also, even though I have a 2015 model, my lines were the newer style, not the older style. Just something to think about if you plan to order the new housing, look under the truck first and see what style you have, not all 2015's were the old style apparently.

I was planning to order the new tsat housing but after the pill flip I'm satisfied with how it runs. Trans shifts great, switching the fluid to Amsoil may have helped too.
It is imperative that it goes back in the correct clocked position. It has passages in the body and if not put back properly it will impede or block flow to the cooler lines.
I guess I got lucky, I did not pay attention to the position of the cap when I put mine back together.
 

Tonyv__

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A few things after having the pill flipped for a few months now. Temps are great, usually around 140 empty, up to 175 or so light towing. Much better than the near 200 it was at before. Also, even though I have a 2015 model, my lines were the newer style, not the older style. Just something to think about if you plan to order the new housing, look under the truck first and see what style you have, not all 2015's were the old style apparently.

I was planning to order the new tsat housing but after the pill flip I'm satisfied with how it runs. Trans shifts great, switching the fluid to Amsoil may have helped too.

I guess I got lucky, I did not pay attention to the position of the cap when I put mine back together.

I’m considering doing this to my 2015 Yukon…. One thing I haven’t seen in any of the videos, do I need to replace any gaskets? Like is there a gasket from the thermostat block to the transmission that I’ll need to replace?
 

Prospect62

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I’m considering doing this to my 2015 Yukon…. One thing I haven’t seen in any of the videos, do I need to replace any gaskets? Like is there a gasket from the thermostat block to the transmission that I’ll need to replace?
This mod (at least doing it this way with GM parts) is only applicable to the 2016 and newer trucks. The 2015 and older trucks use a different quick release type fitting on the cooler lines that aren't compatible with the updated TBV part #86774933 (thermal bypass valve).

There are still DIY or aftermarket ways you can accomplish the same thing. This, for example, will do the same thing and should work with your 2015...


The lines themselves don't have a seal on your application. On the newer trucks they have an o-ring (but these don't really need to be replaced anyway). There is, however, a gasket that goes between the thermostat and the transmission body:


But that seldom has to be replaced either. You could do it as cheap insurance, and I would.
 

Tonyv__

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This mod (at least doing it this way with GM parts) is only applicable to the 2016 and newer trucks. The 2015 and older trucks use a different quick release type fitting on the cooler lines that aren't compatible with the updated TBV part #86774933 (thermal bypass valve).

There are still DIY or aftermarket ways you can accomplish the same thing. This, for example, will do the same thing and should work with your 2015...


The lines themselves don't have a seal on your application. On the newer trucks they have an o-ring (but these don't really need to be replaced anyway). There is, however, a gasket that goes between the thermostat and the transmission body:


But that seldom has to be replaced either. You could do it as cheap insurance, and I would.
Thank you for the detailed response
 

Rygrego

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Just installed the updated TCV (thermostat) for my 6L80e. Took about 30 min once I found the correct size sockets and got set up. Trans temp now doesn’t go about 150. Part was about 50 bucks. Part number is 86774933 if anyone is interested. I think it’s well worth it.
Been there, done that. I think you'll find it was a good move.
 

tom3

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Anyone have any luck actually ordering the trans. temp. control valve lately? I've been all over the net trying to order this and just keep going around in circles. GMpartsdirect's cart only offers a quote via email, then goes back to the order page, click to get email quote again, no way to actually order. Other companies' pages either say invalid VIN or just goes to a blank page. Anyone got any help on this? I do see an aftermarket kit on Amazon to convert my OE valve to the lower temp but I'd sure rather use GM parts on this newer machine.
 

tom3

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I did find one at Hendricks and the order process went all the way to shipping, but at near $40 shipping for that little piece of jewelry, well, still looking.
 

travisk

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Just replaced TBV in a fresh 6l80 GM reman that was installed in my 2015 tahoe. Literally a 20 mins job start to finish. Don't know if they're were torque specs but the bolt that bolted the TBV to the tranny seem very snug when breaking loose and the one that bolted the plate that holds the lines to the TBV seemed almost loose. I used the "Gutentite" torque method when I put it back together.

Typically idled at 194 degrees now idles at 174 degrees :( . Seems like a waist of 100$
It is hot a hell here in North Texas now tho. Except the fact we just broke a 21 day streak of 100+ degree days yesterday and today. Was expecting more of a drop with this cold front. Back in the 100s starting tomorrow. So the tranny temp is likely to be even higher tomorrow.

And good luck finding the o-rings for the lines. Neither dealership in my area had em. Guess you can order em online and wait. Luckily I have a o'reilly's warehouse in my area that lets you do will call. I was able to at least pick up the seal/gasket that goes inbetween the tranny and TBV. No autozone, o'reillys or napa had the acdelco one instock. And only napa had a aftermarket one in stock for twice the cost..
Ended up not replacing the old o-rings, hope that doesn't come back to bite me.. Seems to be doing fine so far. Stuck my head up under there after several drives today and narry a drip.

Also seems like people are saying the 2014-2015 models had the quick disconnects for the lines. Mine had the plate that works with this TBV. The stealership didnt say they changed the lines when they did the tranny so I'm going to assume they didnt since it wasn't on the bill. Think mine is a 2015.5 tho.


1. They've identified heat being a issue with these. Wonder why they're not being put into the remans to begin with?
2. Any particular reason 2014 and 2015 years were removed from this TSB in the latest revision?
3. Anyone know if theyre still using the same torque converts that like to blow up around 100k with their remans?
 
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Sparksalot

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Just replaced TBV in a fresh 6l80 GM reman that was installed in my 2015 tahoe. Literally a 20 mins job start to finish. Don't know if they're were torque specs but the bolt that bolted the TBV to the tranny seem very snug when breaking loose and the one that bolted the plate that holds the lines to the TBV seemed almost loose. I used the "Gutentite" torque method when I put it back together.

Typically idled at 194 degrees now idles at 174 degrees :( . Seems like a waist of 100$
It is hot a hell here in North Texas now tho. Except the fact we just broke a 21 day streak of 100+ degree days yesterday and today. Was expecting more of a drop with this cold front. Back in the 100s starting tomorrow. So the tranny temp is likely to be even higher tomorrow.

And good luck finding the o-rings for the lines. Neither dealership in my area had em. Guess you can order em online and wait. Luckily I have a o'reilly's warehouse in my area that lets you do will call. I was able to at least pick up the seal/gasket that goes inbetween the tranny and TBV. No autozone, o'reillys or napa had the acdelco one instock. And only napa had a aftermarket one in stock for twice as cost..
Ended up not replacing the old o-rings, hope that doesn't come back to bite me.. Seems to be doing fine so far. Stuck my head up under there after several drives today and narry a drip.

Also seems like people are saying the 2014-2015 models had the quick disconnects for the lines. Mine had the plate that works with this TBV. The stealership didnt say they changed the lines so I'm going to assume they didnt since it wasn't on the bill. Think mine is a 2015.5 tho.


1. They've identified heat being a issue with these. Wonder why they're not being put into the remans to begin with?
2. Any particular reason 2014 and 2015 years were removed from this TSB in the latest revision?
3. Anyone know if theyre still using the same torque converts that like to blow up around 100k with their remans?
You got lucky on that plate retainer. My 2015 has the quick release style. Pita.
 

Prospect62

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Ended up not replacing the old o-rings, hope that doesn't come back to bite me.. Seems to be doing fine so far. Stuck my head up under there after several drives today and narry a drip.

You shouldn't need to change the O-rings anyway.

Also seems like people are saying the 2014-2015 models had the quick disconnects for the lines. Mine had the plate that works with this TBV. The stealership didnt say they changed the lines when they did the tranny so I'm going to assume they didnt since it wasn't on the bill. Think mine is a 2015.5 tho.

That's very odd.


1. They've identified heat being a issue with these. Wonder why they're not being put into the remans to begin with?

3. Anyone know if theyre still using the same torque converts that like to blow up around 100k with their remans?

These are two questions I wanted to ask when I had my 6L80 replaced in January but I never did. I did my TBV and hoping it makes the new trans last longer but I really don't care all that much as I most likely won't have the truck for another 100,000 miles.
 

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