2014 Sierra trans thermostat part numbers

[RobbyDawg]

I have a 2014 Sierra and attempted to perform the pill flip, however I live in Ontario and our road salt has thoroughly corroded the thermostat housing to the point that opening it up proved impossible. 
 

I want to perform the TSB to replace the stat with part number 86774933.  I know the cooler lines are different and will require replacement for this to work.  Does anyone have the correct part numbers for what I require?  I called the dealer and predictably, they were absolutely useless…the parts guy couldn’t have cared less.  
 

I read here that 85132191 is the part number for the entire thermostat and lines assembly but am not sure if this fits my 2014.  I don’t think it does bc my truck has the lines going into drivers side of radiator whereas the descriptor for that part number says “Wo atf cooling connections on left side of radiator.”  Does anyone know for sure?

 

Edited August 29, 2022 by RobbyDawg

[RobbyDawg]

After much searching I’m 99% sure the correct part is 23370657.  Stealer has them in stock so I’ll be able to check it out before plunking down my cash.  

Edited August 29, 2022 by RobbyDawg

[Black02Silverado]

Good that you can check it out.  The main individual on here that would know is not on often anymore.  Let us know what you find out.

[RobbyDawg]

So, I bought the 23370657 from the dealer. The included TBV did NOT have a 70 stamped on the bottom, but I bought it anyway because I needed the lines.  I don’t believe the lines can be purchased without the TBV.  
 

Anyway, I installed them (fit perfectly) and sure enough trans temp went up to 190 ish.  
Was thinking of buying updated TBV on its own, but I’m going to try the pill flip first now that I’ll be able to actually get the darn thing apart.  I live in cold climate so was thinking against this with the concern of over cooling. However, on my 2014 the ATF goes through the engine radiator then the air to oil cooler so it might be okay.  I’ve got nothing to lose by trying it.  

 

Sheesh…after I get this sorted out hopefully I’ll have a reliable truck for many years to come.  Already had a custom tune done to turn of AFM and modify TCC logic.

Edited September 5, 2022 by RobbyDawg

[14burrito]

20 hours ago, RobbyDawg said:

So, I bought the 23370657 from the dealer. The included TBV did NOT have a 70 stamped on the bottom, but I bought it anyway because I needed the lines.  I don’t believe the lines can be purchased without the TBV.  
 

Anyway, I installed them (fit perfectly) and sure enough trans temp went up to 190 ish.  
Was thinking of buying updated TBV on its own, but I’m going to try the pill flip first now that I’ll be able to actually get the darn thing apart.  I live in cold climate so was thinking against this with the concern of over cooling. However, on my 2014 the ATF goes through the engine radiator then the air to oil cooler so it might be okay.  I’ve got nothing to lose by trying it.  

 

Sheesh…after I get this sorted out hopefully I’ll have a reliable truck for many years to come.  Already had a custom tune done to turn of AFM and modify TCC logic.

 

You have a V6?

 

I thought the V8 routed ATF via condensor.

[RobbyDawg]

On 9/6/2022 at 4:12 PM, 14burrito said:

 

You have a V6?

 

I thought the V8 routed ATF via condensor.

2014 and I believe 2015 trucks route atf first to radiator then condenser cooler.  
 

I did the pill flip today and didn’t see trans  temps above 170F.  We’ll see how it does in 5 months when it’s -20!  

[Grumpy Bear]

1 hour ago, RobbyDawg said:

2014 and I believe 2015 trucks route atf first to radiator then condenser cooler.  
 

I did the pill flip today and didn’t see trans  temps above 170F.  We’ll see how it does in 5 months when it’s -20!  

 

It will do just fine. Run just like they did the first hundred years without a thermostat. 

[14burrito]

1 hour ago, RobbyDawg said:

2014 and I believe 2015 trucks route atf first to radiator then condenser cooler.  
 

I did the pill flip today and didn’t see trans  temps above 170F.  We’ll see how it does in 5 months when it’s -20!  

 

Uhh, if that the case....I don't get it.

 

Crack temps:

ATF thermostat is 180

Coolant is 207

 

The ATF full open is less than the crack temp of the coolant thermostat...

 

So they warm the ATF to cool at the condensor? 

Edited September 11, 2022 by 14burrito

[Grumpy Bear]

3 hours ago, 14burrito said:

 

Uhh, if that the case....I don't get it.

 

Crack temps:

ATF thermostat is 180

Coolant is 207

 

The ATF full open is less than the crack temp of the coolant thermostat...

 

So they warm the ATF to cool at the condensor? 

 

Yep. Dizzy right? The idea was to get the fluid up to temp quicker. Then there is this. The 207 F temp is the engine outlet temperature. Radiators job is to lower that to something lower, right? Like about 20 to 30 F lower for a fin fan exchanger which a radiator is. 

 

Thing is the V8's uses the hot side as the cooler while the V6 uses the cold tank as the cooler which means for the V8 to cool the inlet ATF temp has to be above 207 F and it is. So the hot side is a first stage cooler then off to the condenser for about 20 F more. The V6 doesn't use the AC condenser. Just the cold tank. No idea why they complicated a hammer like this but is what it is. They both end up the same. The V6 just uses less equipment to get there.  

 

Mine is a V6 and for some time I did the pill flip. Recently I installed the 70C thermostat and guess what? It runs warmer in the winter and the same in the summer as the flip. Needs more cooler than the factory set up to maintain the throttling temperature of 148 F on days with ambient temps over 80 F. I'll get to it. 

[RobbyDawg]

12 hours ago, Grumpy Bear said:

 

Yep. Dizzy right? The idea was to get the fluid up to temp quicker. Then there is this. The 207 F temp is the engine outlet temperature. Radiators job is to lower that to something lower, right? Like about 20 to 30 F lower for a fin fan exchanger which a radiator is. 

 

Thing is the V8's uses the hot side as the cooler while the V6 uses the cold tank as the cooler which means for the V8 to cool the inlet ATF temp has to be above 207 F and it is. So the hot side is a first stage cooler then off to the condenser for about 20 F more. The V6 doesn't use the AC condenser. Just the cold tank. No idea why they complicated a hammer like this but is what it is. They both end up the same. The V6 just uses less equipment to get there.  

 

I wonder if the 2014/‘15 design is a carry over from 2013 and prior models which as we know had no trans stat.  Since the  trans t-stat is closed until 180, there’s no warming of the ATF going on at all.  Now with my pill flipped the ATF is actually warming faster which might prove beneficial to fuel economy, (very slightly).