Jump to content

K2XX Trans Cooler Thermostat Thoughts and Opinions

newdude
 Share

Recommended Posts

dieselfan1 Senior Enthusiast

dieselfan1

Posted
Posted

I'm keeping mine flipped.

Even when it's -15°F it runs cool never hits 100°.

My truck is lifted and running 38s .

It shifts fine.

I'm making some more popcorn. Carry on.

  • Like 2
  • Thanks 1
  • Replies 74
  • Created
  • Last Reply

Top Posters In This Topic

Popular Days

Top Posters In This Topic

Popular Days

Popular Posts

newdude
newdude

Part Three:  My experience and suggestions for those looking to make a move on one of these options   On my 2019 K2 Silverado, I have now experienced both the Sure Cool kit, and now the GM l

16LT4
16LT4

There's your answer right there.  Your truck has only the ATF-air cooler (not liquid-liquid heat exchanger in the radiator), so is using predominantly vehicle speed to move air across the cooler (with

newdude
newdude

Some notes worth mentioning:   2014 K2 owners.  You NEED to replace the transmission cooler lines to use GM's new thermostat.  The thermostat is designed to fit the second design cooler line

Posted Images

pokismoki Senior Enthusiast

pokismoki

Posted
Posted

most componenets in the trans can handle 190-200 F,  the weak link are the rubber seals. they are what controls pressure to the clutches, and maintains pressure in solenoids and signal pressure to the sensor switches.   ask yourself how long did those brand new rubber wiper blades last on your windshield back in the day. i could never get them to live more than a year with the thermal oxidation from sun roasting them in the the summer.. this is the same problem the 6L80 has with it's rubber seals and O-rings

 

they say the torqueconverter is atleast 100F hotter than whats dispalyed on the DIC,  and on the snout of the trans pump is a rubber O-ring that gets cooked to death. it's responsible for controlling pressure in the Lock up in the converter

  • Like 1
rav3 Senior Enthusiast

rav3

Posted
Posted
1 hour ago, dieselfan1 said:

I'm keeping mine flipped.

Even when it's -15°F it runs cool never hits 100°.

My truck is lifted and running 38s .

It shifts fine.

I'm making some more popcorn. Carry on.

I'm with you bro! AFM deleted too. Mine shifts fine as well, even smoother when cold. I guess GM thought it was wrong too since the revised the TBV with all transmission services! Go figure...doesn't take a rocket scientist to figure this one out.

rav3 Senior Enthusiast

rav3

Posted
Posted
29 minutes ago, pokismoki said:

most componenets in the trans can handle 190-200 F,  the weak link are the rubber seals. they are what controls pressure to the clutches, and maintains pressure in solenoids and signal pressure to the sensor switches.   ask yourself how long did those brand new rubber wiper blades last on your windshield back in the day. i could never get them to live more than a year with the thermal oxidation from sun roasting them in the the summer.. this is the same problem the 6L80 has with it's rubber seals and O-rings

 

they say the torqueconverter is atleast 100F hotter than whats dispalyed on the DIC,  and on the snout of the trans pump is a rubber O-ring that gets cooked to death. it's responsible for controlling pressure in the Lock up in the converter

To each their own decisions. Go ahead & run yours as hot as you want. That is fine with me. We all do what we do cause we want to. Enjoy your truck....

Black02Silverado Senior Enthusiast

Black02Silverado

Posted
Posted

@newdude, great post and a ton of information.  Thanks for posting this.  Everyone that has a 2014 and up with the 6l80 and 6l90 would greatly benefit to changing out their thermostat.  As newdude stated GM even realized the issue.

 

I feel that one would benefit from changing out the thermostat and switching over  to a quality synthetic ATF like AMSOIL.  My good fortune with all my transmissions has been the fact that I switched all my vehicles over to AMSOIL ATF pretty much right away.  My 2002 Silverado I had the dealer do a full exchange at 5k miles on the truck.  I did a pan drop and fluid change at 75k miles.  That post is here.  I then switched over to AMSOIL's ATL fluid when they came out with it back in 2006.  I pulled the cooler line and did a fluid exchange.  This was around 100k miles on the truck.

 

I switched over the 2016 Suburban at 10k miles and just did the 2019 Silverado with the 10sp at 25k.  Why so late on it?  Well I was hoping someone would come out with a Youtube on how to do it yourself.  Well it never happened due to the fact that, to my knowledge, the fill plug is on top of the transmission and you really can't get to it.  The dealer fills it back through the cooler lines and then  checks the fluid from the side level port at a certain operating temperature.  I've had the AMSOIL ATL in it now for over 1,000 miles and it shifts great.  To me it has a crisper shift if that makes sense.

 

Then time got away from me and before I knew it I hit 200k and I did a pan drop and fluid change.  I sent a sample off and the results came back good.  In that 100k mile time frame I started towing on occasion, a 10'x20' box trailer for Ainsley's Angels and the weight of the trailer is just under 4,500lbs.

 

Again, installing the  lower temp thermostat and a quality synthetic fluid will keep the transmission running smooth for a long time.

 

One thing I forgot to mention is I change out the transmission fluid every 50k miles in all my vehicles. My 2014 Cruze diesel's transmission runs at 220°F to 225°F according the the Scan Gauge II I have hooked up to it.  Way to hot but it is what it is.

  • Like 1
steelerdude15 Enthusiast

steelerdude15

Posted
Posted (edited)

Thank you for the write up @newdude. I flipped my pill when I changed my fluid and filter at 30,000 miles. I’m 100 miles shy of 38,000.  So far everything is fine. When I change my fluid and filter at 60,000 miles, I’ll consider the new thermostat at that time. Then we’ll know for sure how the new thermostat has held up since it’s release.

Edited by steelerdude15
  • Like 1
YYC-SIERRA Enthusiast

YYC-SIERRA

Posted
Posted

Slightly off-topic, but what kind of transmission temps are guys experiencing when driving in 4x4 LO for extended periods of time? 

 

I flipped my pill 1 month ago, everything has been great so far. Averaging 60C / 140F on the highway. The other day I was driving up a steep and rough mountain road (Popocatepetl Volcano - south of Mexico City) and since I rarely use 4x4, I tried it out for a while. After 15 minutes, the trans was about 98C / 208F so I switched back to 2WD, it decreased slightly. 

 

Is this pretty normal for 4x4 LO to run the transmission so hot? The only other time I've ever approached 100 C was pulling a 7000 lb trailer over the Eisenhower Pass in Colorado. 

 

 

Screen Shot 2022-01-28 at 21.06.48.png

  • Like 1
Grumpy Bear Senior Enthusiast

Grumpy Bear

Posted
Posted
2 hours ago, YYC-SIERRA said:

Slightly off-topic, but what kind of transmission temps are guys experiencing when driving in 4x4 LO for extended periods of time? 

 

I flipped my pill 1 month ago, everything has been great so far. Averaging 60C / 140F on the highway. The other day I was driving up a steep and rough mountain road (Popocatepetl Volcano - south of Mexico City) and since I rarely use 4x4, I tried it out for a while. After 15 minutes, the trans was about 98C / 208F so I switched back to 2WD, it decreased slightly. 

 

Is this pretty normal for 4x4 LO to run the transmission so hot? The only other time I've ever approached 100 C was pulling a 7000 lb trailer over the Eisenhower Pass in Colorado. 

 

 

 

 

How fast were you driving? What was the ambient temperature? 

 

image.png.aacd1d05eee8741dd2fe83773180bfcc.png

  • Like 1
customboss Senior Enthusiast

customboss

Posted
Posted
14 hours ago, YYC-SIERRA said:

Slightly off-topic, but what kind of transmission temps are guys experiencing when driving in 4x4 LO for extended periods of time? 

 

I flipped my pill 1 month ago, everything has been great so far. Averaging 60C / 140F on the highway. The other day I was driving up a steep and rough mountain road (Popocatepetl Volcano - south of Mexico City) and since I rarely use 4x4, I tried it out for a while. After 15 minutes, the trans was about 98C / 208F so I switched back to 2WD, it decreased slightly. 

 

Is this pretty normal for 4x4 LO to run the transmission so hot? The only other time I've ever approached 100 C was pulling a 7000 lb trailer over the Eisenhower Pass in Colorado. 

 

 

Screen Shot 2022-01-28 at 21.06.48.png

If you are from Calgary do you run Amsoil or synthetics in the drivetrain?  4LO on my 2022 LTD 2.7L T Trail Boss Custom is a tractor gear, going 30 mph is too fast.  At least in the snow here.  You get around Bro!  

  • Like 1
lawnboy-5247 Enthusiast

lawnboy-5247

Posted
Posted (edited)

Also slightly off topic but My transmission cooler lines are starting to leak in the flexible hose portion and I know that the lines include the thermostat but I am unsure which part number GM is using with the hose set. Does anyone know if the new part number thermostat is being included with the transmission cooler line sets?

Edited by lawnboy-5247
pokismoki Senior Enthusiast

pokismoki

Posted
Posted
17 hours ago, YYC-SIERRA said:

Slightly off-topic, but what kind of transmission temps are guys experiencing when driving in 4x4 LO for extended periods of time? 

 

I flipped my pill 1 month ago, everything has been great so far. Averaging 60C / 140F on the highway. The other day I was driving up a steep and rough mountain road (Popocatepetl Volcano - south of Mexico City) and since I rarely use 4x4, I tried it out for a while. After 15 minutes, the trans was about 98C / 208F so I switched back to 2WD, it decreased slightly. 

 

Is this pretty normal for 4x4 LO to run the transmission so hot? The only other time I've ever approached 100 C was pulling a 7000 lb trailer over the Eisenhower Pass in Colorado. 

 

 

Screen Shot 2022-01-28 at 21.06.48.png

how does it run in 4wd Hi vs 4Lo?

 

you could be on an incline and  may not be moving the truck fast enough to engage tcc lock up, so the torque converter is over working the fluid and creating lots of heat, or vis versa, you need to data log the trans with tuning software to know whats happening inside 

 

try using Manual gear M4 instead of D drive

 

  • Like 1
YYC-SIERRA Enthusiast

YYC-SIERRA

Posted
Posted
21 hours ago, Grumpy Bear said:

 

How fast were you driving? What was the ambient temperature? 

 

image.png.aacd1d05eee8741dd2fe83773180bfcc.png

 

SORRY mental block......i meant 4HI, i was in 4HI crawling up this rough AF road for probably 20 minutes, never getting out of 1st gear. Temps were probably 45-55F outside, but it was also above 10,000 feet. 

 

I've used 4LO I think once in my truck's life, on a steep boat ramp pulling a boat out for 10 seconds, that's it. 

 

Awesome graph, thanks for that info. Seems to explain it well, seems like nothing to worry about, given the conditions.

 

I use Amsoil in both diffs, with GM Dex 6 in the transfer case and transmission. 

 

  • Like 2
NE18 Enthusiast

NE18

Posted
Posted

I went up Mt. Washington in D and saw temps 200-210. For some reason, after watching TFL truck and listening to Mr. Truck say higher RPMs cools the transmission better, i went up a smaller mountain, locking out the higher gears (I think I limited the gears to 1st and 2nd) and the temp went up to 230. Maybe you being in 1st the whole time was the culprit?

  • Like 1
16LT4 Enthusiast

16LT4

Posted
Posted (edited)
On 1/29/2022 at 11:05 PM, YYC-SIERRA said:

 

but it was also above 10,000 feet. 

 

 

There's your answer right there.  Your truck has only the ATF-air cooler (not liquid-liquid heat exchanger in the radiator), so is using predominantly vehicle speed to move air across the cooler (with some fan action, but the fan is pulling most of the air through the engine coolant's radiator).  With reduced air flow (presumably going slower when in 4WD due to the terrain requiring 4WD), increased resistance (heat) in the transmission (turning the extra axle), coupled with air that is less than 65% as dense as at sea level, it's no surprise you saw increased heat.  The dry air at that altitude also has less ability to absorb and retain heat than humid air, too. :)

Edited by 16LT4
  • Like 4
pokismoki Senior Enthusiast

pokismoki

Posted
Posted (edited)

yes  you need to reprogram the fan settings and install a kateck 175 t-stat for that kinda work out these trucks weight about 5500lbs , you should be in 4LO for inclines to utilize torque, and disable TCC function for  gears 1,2, and 3

9 hours ago, NE18 said:

I went up Mt. Washington in D and saw temps 200-210. For some reason, after watching TFL truck and listening to Mr. Truck say higher RPMs cools the transmission better, i went up a smaller mountain, locking out the higher gears (I think I limited the gears to 1st and 2nd) and the temp went up to 230. Maybe you being in 1st the whole time was the culprit?

Edited by pokismoki

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Latest Articles

  • Posts

    • Chuck FB
      Fluid Change Questions

      By Chuck FB · Posted

      There would be one way of determining the quality of the factory oil although probably more than a typical oil lab test, and that would be to draw out some oil from a new truck and send a sample to a lab that could do a more elaborate test of the oil. The issue with too little oil in the diff may not be the lack of lubrication of the diff bearings and gears themselves ( although a lack of oil volume for cooling ) but the wheel bearings because at some point the oil would be too low to properly get onto the spinning axle or fed along the axle tube. That was the claim by the local dealer from a couple of trucks in recent years that had the wheel bearings fail and they figured from lack of sufficient oil due to a severe underfilled diff and some of the bearing material made its way to the diff and it got damaged as well so the axle housings were just replaced on warranty. But your right that if the diff is over filled by whatever margin that it causes more churning of the oil than is desirable and that is no good either and can cause a pinion seal to leak. Also old oil I believe can tend to loose some of its properties like antifoaming and another good reason to change the diff oil every so often. 
    • Z45
      Fluid Change Questions

      By Z45 · Posted

      I would be surprised if the diff's were not filled (with the cheapest gear lube) at the axle factory before being shipped to GM.  If you ever watched them building trucks they install the axles and all suspension parts with the frame upside down and then turn it over before its time to install the engine.     Too much gear lube in a axle can be worse than not enough especially with a lower quality GL where is get whipped up with entrained air (foam)  weakening its ability to lubricate.        
    • MORSNO
      Oil Consumption

      By MORSNO · Posted

      This is the 6.6 gasser section of the forum, you should either delete or modify your previous post as it is misleading for anyone looking for factual information on their 6.6 gas engine.
    • Atlas
      Wow I'm in a pickle. (Broke down truck) and a story.

      By Atlas · Posted

      Well....I've done my first intake gasket. Probably wrong, but...we'll see?   Ultra black on the china walls and 1/4" up onto the sides of the intake gaskets. Permatex High Tack (couldn't find Gaskachinch) on the head side of the intake gasket. I read wrong and it says you're supposed to put it on the mating surface of the head, not the gasket. Hoping it's like a PB&J sandwich where it doesn't matter what side the PB goes on so long as there's jelly. That crap is messy/sticky and I got a dab or two on the intake port openings, tried to wipe it off. Hopefully it won't be a big deal and will only aid in sealing.   Per instructions I left the intake (top side) of the gasket dry except for a light smear of RTV around the coolant ports. Wiggling the intake in there was a bear but I had help to free me of surrounding wiring/stuff but I was basically able to set it straight down lined up with the bolt holes.   I did not think to wait until the RTV skinned over but there probably was 5-10 minutes while it sat before installing the intake.   Bolts finger tight first. Then, followed the Chilton's manual pattern to snug them to 15 lb-ft.   Waited a little over an hour, and then did the final torque in sequence again to 35 lb-ft.   Yesterday I replaced the fuel pressure regulator and got my new "nut and bolt kit" (fuel lines) installed. Damn GM used security torx on the spider, which I don't have, so I got scammed at the local HW store for an off-brand security Torx bit set.   The new driver's door mirror arrived yesterday, so, there's a chance this thing could be running and road legal tomorrow? I don't want to get my hopes up.   This will be my first time stabbing a distributor, too. Although, lucky me, someone else marked the old distributor for removal previously, I did see that. (Someone's been here before!!). Engine is still at TDC so it *should* be just a matter of transferring the mark to the new dizzy and rotating it into place.
    • KARNUT
      2027 GMC Sierra: Official Discussion

      By KARNUT · Posted

      He has his dad’s newer truck he’s put away. He has several old cars he rotates between him and his family. I’ve seen a restored square body and a SS Chevy truck he’s sometimes drives. He did raffle off a new suburban recently. As much as he is watched if he drove new stuff as a rule we’d know it. It would be fine by me. I don’t care what people prefer. I got one more new one in me. I’d rather my wife get one. I can’t get her out of the Genesis. Don’t tell anyone. I want her to get an electric truck. I want to put a generator in the back. Just because. She hasn’t bit yet.

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...