GM Silverado Sierra Transmission Cooler Line Replacement & Thermostat Delete (2014 +)

[@14burrito2]

FYI to anyone watching this. GM issued a TSB Sept 27th 2021 for a lower temp ATF tstat unit. TSB 21-NA-199. The unit now uses a 158F vs 194F.

[@CharlieAtkins]

You do NOT need a thermostat on a transmission cooler period... Needs to be bypassed altogether.👍

[@ClaudeTaylor-i3i]

just did replaced the lines on a 2016 4 WD. thank you! one thing to add I ran a string to help guide the new lines between the cross member/ front drive axle and all of the wire loom. the tip on the spring clip was a big help also.

[@lkazanov]

Finally....I understand the transmission cooler line routing. 3/8" lines. BTW....I believe the line shown on the drivers side is TO THE cooler and the upper line on the passenger side is the RETURN line to the transmission. The passenger female connector is what I will tap into to drain the fluid with the transmission pump.

[@HuntMountain06]

This is exactly what I was looking for. Which line is feed and which is return.

[@TheClamSlam160]

This was a awesome video. My truck has 4WD so i had alot of extra crap to work around. Help me alot thanks!

[@Acurakiller]

Phenomenal video with great info while working it. Great video shots as well. You the man!! Thank you!

[@AaronHinesAuto]

Thank you! Glad it was helpful

[@Ls_swap211]

So glad I seen this !!! I got 10” lift and 37s with 4.56 gears in my 2016 and it ran at 202° on level highway so I flipped my plunger and 155° is the highest so far I’ve seen in Wv 75° ambient temp so far Thanks !!!

[@benjaminalmendarez3059]

I have a lifted 2013 Silverado 9" lift which tires claim to be 37x12.50r22 but tires really measure 36.5 inches tall and no they're not stretched cause they're on 22x12 wheels, mine has 4:56 gears Detroit trutrac boltons & a custom tune from a local performance shop had the engine tuned & the 6l80 also with a 40k trucool never saw temps over 130 in hot texas summer days 140ish when towing but it messed up even though it was tuned but still had stock interns which they werent to pair with the 4:56 gears so now It has a stage 1 performance 6l80e built upgraded forged interns & tuned specially for 36.5 " tires 4:56 gears but will be installed this weekend I hope also never believe whats posted on a tire so grab a tape measure and get true height also download a speedometer app make sure you're pickup truck is not under miles. All this is from experience with my 2013 silverado 4wd

[@Ls_swap211]

@@benjaminalmendarez3059 yep I’ve personally never seen a true size tire yet lol Vehicle weight usually accounts for .75” but the tire themselves are always 1” smaller before mounted I no longer have my lifted truck but It had roughly 210k when I wrecked it with no probs other then converter failure early in its life

[@benjaminalmendarez3059]

@@Ls_swap211 the thing that pisses me off mine has toyo open country mt 37x12.50 I paid $2300 for tires with them being balance & mounted why are they so expensive if they're not the size they claim to be

[@Ls_swap211]

@@benjaminalmendarez3059 I ran Mickey Thompson Mtz p3 and got better mileage then Toyo for a little less price but I paid $1800 for 4 and kept them rotated every 3000miles or so Back when I had 35s I thought I was doing good till they barely measured 33” lol

[@benjaminalmendarez3059]

@@Ls_swap211 thats why alot cant get the speedo correct cause they put size thats claimed on tires which its not the true size

[@jessebynog1323]

Had a 4×4 got another chevy great video thanks.

[@abasin08]

Hey Aaron, other than the lines leaking, what would be the main reason you would want to replace the lines? I tried to understand some of the comments, thank you.

[@chasec4478]

Watched your other video for the thermostat delete and could I just flip the thermostat like this instead of tapping a hole and putting a plug?

[@AaronHinesAuto]

yes, there are two ways to do this mod, flipping the thermostat works good on trucks that arnt being pushed to the max. on vehicles that are pushed hard (big tires, high hp, heavy towing, outside temps over 110) i recommend tapping the block as it allows for more flow to the cooler, flipping the thermostat does the same but i have seen greater results with the plug method.

[@spookman4917]

Did you all notice the proximity of the catalytic converter to the cooler lines? The fluid was baked already! Great Video!!

[@93gmctruck18]

Nice bro I did this to my 2015 Cadillac Escalade I put a tap bolt and flush the transmission n replace filter n welded a bolt to pan for easy drain for next time.

[@ronaldlewis4032]

I was going to order the bypass but with your knowledge I won't need it now,I'll follow your instructions 😉

[@advert25]

Ah yes! This is the video I have been looking for. Going to delete the thermostat on my Silverado. Towing a travel trailer and it gets way to hot. Scratching my head why GM would add a thermostat on the transmission making it get so hot.

[@andrewpeters87]

It's not the thermostat, its your ability to remove the heat after the thermostat is open, you probably need a bigger transmission cooler when hauling a camper. 180-200 deg should be normal temps

[@advert25]

@@andrewpeters87 I ended up getting a 2019 Silverado with the transmission cooler and tow package. Stays nice and cool now with no problems now. :)

[@CharlieAtkins]

@@andrewpeters87 It IS the thermostat fella, ever wonder why GM didn't put them on 2500 and 3500's... Ots on there so GM could achieve the fuel economy standards... 👍

[@kurtlarson1151]

@@andrewpeters87 not correct. 190/200 is way to hot. His thermo operating correctly.. It's just that what GM says to oper at 192, not for good life of trans.

[@kurtlarson1151]

@@CharlieAtkins exactly. They are not doing these things in your vehicles best interest.....period. Like he said, it's for mileage. They WANT your vehicle to have issues after 100K.

[@paflyer1370]

Will doing this mod hurt the transmission during cold winter months? I plan on towing a heavier travel trailer, but probably won’t be pulling it much in the winter

[@CharlieAtkins]

NO...

[@kurtlarson1151]

Just watch the transmission temps. If it ends up running well over 100, your fine in winter months. But if not, GM does make a 158 degree valve to replace the 192F thermostat valve. ne w158 part # is 86774933

[@singhbling5190]

So reversing the thermostat will help with cooling? Delete of the thermostat ?

[@Terpedup925]

Chevy wants $610 to do this work. I’m nervous to do it myself but I’m gonna try. All I have a floor jack not a lift so it might be tricky. Thanks for the video

[@Antony-q7w]

Same bro my nearest Gm dealer wanted 800$ in labor for both my engine cooler lines and transmission lines did it my self watching you tube videos saved my ass 800$

[@samnishi4801]

Great video, thank you> Love the step by step, you made it easy. Now I need to find a video to replace the engine cooling line.

[@lawnmoose]

This video is so good. Thanks!

[@michaelclark6506]

I guess I have the newer version you installed .to preform a thermo delete do I just leave it on the truck ? Will the lines come out the thermostat

[@1200s-e8n]

Will this method of deleting the thermostat work on a 2012 GMC YUKON 5.3L SLE?

[@jbyfaith06]

Awesome video! I was amazed how well you were able to video what you were doing clearly so your viewers can follow everything you were doing. Question: Should I get the replacement line from a Chevy dealership? I have a 2014 Silverado High Country 1500 5.3 engine. Thanks in advance!

[@jmovision270]

Ok what’s the difference in doing your bypass mod then buying the sure cool bypass kit do I need it or just run your way I got a 40k cooler and I’m still getting 196 on highway

[@mishutkin101]

I installed the stl010 bypass and it was working great until I replaced my filter and fluid. My temps used to stay around 145ish and now it's getting close 180.

[@garretttuttle9135]

Thank you for making this video. Very informative! I'm going to attach this video to a forum post in regards to flushing transmissions with the torque converter shutters.

[@AaronHinesAuto]

Thank you for sharing! I have a number of how to videos for this truck platform

[@jigga594]

Good video and thorough info!

[@AaronHinesAuto]

Thank you very much!

[@Jeff-dc2xl]

I've got 3 questions. 1st how do you like the valont cold air intake? 2nd can you do this to the 2019-2021 body style? And 3rd how come you don't have a oil catch can installed?

[@CharlieAtkins]

First a CAI is a waste of money without other performance modifications and it will run worse without a tune because you changed the VE (Volumetric Efficiency) tables... And Second, Yes the 19' and up will benefit from the transmission cooler bypass modification... 👍

[@stevens3g]

Ok so at the moment I cannot get under my truck because I slipped a disc in my back. But I had a dealer do the fluid change to stop the shudder, now my lines are leaking. They are not taking responsibility for it and I’m tired of fighting with them. I’m about to order lines and have my buddy throw them in because I can’t work on my own stuff atm. The dealer said “the ac has to be discharged to replace the lines because they go into the condenser,” which I replied I have never seen that for transmission lines it’s always been into the radiator or external cooler and that sounds completely wrong. But I also cannot get under mine right now to call him out or learn something new. I have a 19 trailboss 1500 with the 5.3/8L90… does that sound completely wrong about the ac??? It can’t be true. And I looked at your link for the correct lines for mine and it says cannot confirm fit based off my vin. I have found a couple different part numbers for the 8L90 lines or “pipes.”

[@jasonz28camaro]

any info on the 10 speed? There is no access point either side of the cooler manifold, it must be elsewhere?

[@lkazanov]

Very nice...I am trying to get some guidance on making a barb fitting to the transmission cooler return line so as to flush the transmission. My aim is to attach clear hose to such a fitting and insert into the radiator fitting, top, passenger side. Is this a 3/8" male fitting? Will a Hayden 397 match the male upper hose?? Thanks.

[@jav6635]

Thank you! I have a 2015 Chevy Silverado and this is pretty much the same process.👍🏽

[@michaeliverson8464]

Yes. The Hayden 397 is a perfect fit.

[@Guillotines_For_Globalists]

Would you happen to have the torque spec for the 2 bolts on the thermostat housing?

[@craigquann]

Synthetic trans fluid is rated to 275° the "hot" warning for these trucks are 265°. The thermostat is for transmission efficiency. 190° is the best temp to increase fuel economy. It also lets the transmission warm up faster in cold weather.

[@prettyboyswagproduct]

Wrong Chevy has just released a bulletin with a new thermostat which allows the thermostat to open at 150 instead of 190. The 190 is causing torque converters to burn.

[@prettyboyswagproduct]

You right about the synthetic fluid but in these trucks it’s destroying the torque converter

[@thotslayer8888]

@@prettyboyswagproduct where did you read tht? I am about to replace my transmission cooler lines because it’s leaking, and was wondering if I should try it out without the delete at first. My fluid gets to about 190

[@kurtlarson1151]

@@prettyboyswagproduct you are correct. Few know this.

[@tlwayman]

Will this damage the transmission if I only tow occasionally? My temps without towing get around 195 but I take mostly short trips and it doesnt get higher than 130 normally.

[@BadAssEngineering]

It wont damage the transmission per se, but not heating up the fluid will make it absorb moisture from the air, and water will contaminate it. Same thing happens with engine oil. Just make sure to let the fluids heat up past the dew point in you particular day/area

[@philllsxga.7737]

That thermostat is in there for a reason. Why would GM engineer that into the truck if it wasn't needed?? The thermostat allows for quicker warm up and efficiency. I have no Idea why everyone wants to alter the design of the vehicle. Then they wonder why there vehicles don't last..

[@philllsxga.7737]

If you drive short trips, DEFINITELY do not remove that stat!!!

[@CharlieAtkins]

You just don't get it... Ever wonder why the 2500 and 3500"s don't have one... GM engineers put that on 1500's ONLY to achieve the MPG standards and nothing else.. These transmissions run way too hot and 30% of internal parts are plastic... So I'll let you figure out what happens to plastics at 190°... 😳

[@kurtlarson1151]

@@CharlieAtkins you are correct. Most people don't have a true understanding of what a transmission/vehicle needs as for as oil temp.

[@tylahoh93]

Any tips on how to do a thermostat delete with the new style lines. Is there a way to do it without pulling the whole line since I can’t take the block off by itself

[@bcar1ify]

Remove the bolt on the thermostat that’s between the lines. They will come out at that point

[@joshuagardner110]

Do you keep the spring that’s in the cap in there ?

[@cookingwithpamperedchefkel4911]

Can the main housing be removed without taking all the lines off too? Like the rectangular bracket between the two lines does that “hold it” on the main body? If I remove that can I remove the two lines from the body so I can take the main body off and replace the insides with aftermarket superior solutions

[@cookingwithpamperedchefkel4911]

I got it off. But the snap ring is pretty much corroded in place…. I can’t get the ring off to change out the inside.

[@joshuagardner110]

What about the spring that’s in the cap held in with a clip does that stay?

[@knovelwright4061]

Great video helped me out alot thanks

[@viixiconik]

Will deleting thermostat void my warranty?... plus what if I don't tow and still get up to 196 to 206 degrees? Oh and I also get cold and snowy temperature in the winter time around here.

[@jayer-su3hu]

Common sense says any modification not factory authorized will void the powertrain warranty. That's why I haven't done this to mine yet. Those engineers aren't dumb per se. They know what they are doing by having this thermostat on there. They know heat will kill the transmission. They want it to last just till you get it paid for then it goes down the drain.

[@turtlemaster0001]

Is this a 4x4? Mu Transfercase location seems to be making this task impossible. 4.3, double cab, 4x4,2016 sierra

[@jeffrey.proddd]

does the transmission fluid enter the radiator at the driver or passenger side

[@1_SLOW_WORKTRUCK]

Whats better to tap some threads and cover the hole or just flip the thermostat?

[@Zyphen4866]

I flipped my thermostat and it cost no money and took maybe 30 minutes, highly recommend and you can easily revert back if need be in the winter months.

[@ramair3judge]

The amazon link you provided for the 2014-2016 6L80E is for assy 23370657, however amazon fitment guide says it does not fit my 2014. Is this assy correct for my truck or not?

[@kahoonei_strong]

Do they sell that clamp spring anywhere? The one with the two holes that you need the tool to pinch and remove?

[@kahoonei_strong]

I found it at O’Reilly’s. I did the mod and didn’t put the snap ring on well enough I found out lol. When I turned the truck back on everything went flying off and I ended up losing the snap ring. Got a new one at O’Reilly auto and got it on correctly the second time. The mod definitely keeps the trans fluid cooler a lot longer than before but my temps still get up to low 200’s after a while. But it is summer in AZ so not sure if that’s why or not. Anyway great vid and info

[@jaysrcexpedition]

I got a 2017 Silverado having transmission problems it keeps slipping out of gear but if it sits for a few minutes it will go again but not for long is this a solution to my problem or ?

[@samnishi4801]

Looking for you link to see if i got the right line for my transmission cooling line. Where do i find it?

[@ironlung801]

My temp in my transmission runs 190 - 198 always so i installed a trans cooler but still runs hot. I have the truck programmed for performance mode and keep it in v8 mode. Would you recommend just flipping the trans thermostat at this point because i want to fluid to run into the new cooler i put on or do the plug method?

[@davidchapman1986]

I've read it tries to keep it to up that high to allow for better shifts.

[@ironlung801]

@@davidchapman1986 so flip or plug?

[@davidchapman1986]

@@ironlung801 Sorry - I don't know enough to recommend what to do but I will say my Yukon Denali that I believe has a transmission cooler always ran in the 170-190 range after warmed up. Scouring the forums on an unrelated search it tends to do this to maximize shift performance with warmer fluid.

[@ironlung801]

@@davidchapman1986 so just leave it then?

[@davidchapman1986]

@@ironlung801 I wouldn't change it. If its consistent and not spiking for your driving patterns and use cases I wouldn't change it. The TCC won't lock up if its too cool or you may get harsh shifts. I think Aaron's use case is acceptable, being in Arizona where its always warm. I don't believe the fluid in at least the 8L90's has a problem until you start hitting 240-260ish but my dash gauge doesn't hit red until 300. [edited for clarity]

[@kevinschneider9066]

Nice, but should we worry about the fluid never warming when its -30F here? When towing my RV in the summer, the temperature never exceeds 200F and I wont be towing when -30F. Won't the viscosity of the oil never reach ideal during the cold winters here?

[@kurtlarson1151]

But you said you wont be towing in -30F.

[@123095james]

Which side of the radiator is the outlet for the transmission? Wondering for a transmission fluid flush

[@joshforcha668]

How do you get the cooler lines off of the new thermostat block? I have a 2018 and it’s different than the old housing

[@josuelorenzo5802]

Will the dorman lines work? I can’t find oem ones anywhere

[@davidmason548]

I purchased a new set of lines, however. It came with the thermost block "welded " as one solid unit so I can't fish thr lines through seperate. And thr block obviously won't go through so I can only go back to front from Transmission side. I cannot get them through, I havent tried spinning them around as I too don't have a lift. I was going to disconnect axel and what I believe is an electric motor in same area. Bit you mentioned you only gained about 1/2" when dropping part of axel?? I looked at the part for mine on your link. And it doesn't show seperate lines, it too looks like fixed lines on block now. I believe that's the new,updated version, any advice, ive spent over and hour and a half trying so far

[@davidmason548]

Also, I do not have an extra oil cooler, I have 4WD and a crew cab, of that matters so my connections are different. I guess my part already deletes the thermostat as its much smaller

[@ابوخالدالرويلي-ل5م]

Please why do you increase the depth of the valve housing and is the valve reversible

[@bcar1ify]

What’s the torque spec for the bolt when attaching to trans?

[@matthewhensley6680]

2 Ugg’s

[@JTrump23]

What’s the torque specs ? Not sure what “2 Ugg’s” means lol

[@ChrisEsposito]

I have a 2014 silverado 1500 zr1 . My Torque converter when and wiped out the seal and the temps were reaching well over 208 degrees in normal driving. the trans was banging and miss shifting and surging and shuttering. I just got my truck back today and i asked them before i picked it up did you guys change the thermal bypass valve to the new one .. he said the trans comes with all updated parts.. I do not think he understood what i asked. SO i was driving it easy home and the truck reached 197 degrees and then it must have opened the TBV and it started to cool.. Thats how i knew They did not Change the TBV out for the updated version. I also see transmission fluid dripping from where the Old TBV is installed ... Seal is bad and they did not replaced it before reinstalling it to the new transmission. I called the dealer and told them what i found and that tomorrow morning i will be bringing the truck back and i want the new UPDATED THERMAL BYPASS VALVE INSTALLED WITH THE NEW LINES.... I said i had them on order when i brought the truck in when the transmission was ordered. Im Pissed the hell off.... Im going in and i hope they have all the parts i need to get this done. I do not want to see 195 pop up again on my Trans temp when driving in slow traffic on a cool day.

[@chetdalton3953]

Does that other bolt on the block allow the lines to be separated from the block?

[@bcar1ify]

Yes. Remove that bolt and the lines can be removed

[@juanprenteria5077]

Hello. Can you tell me which line its the one its going back cool to the trans.

[@kurtlarson1151]

it will be the cooler one as you mentioned. Feel it with your hand. Sure fire method.

[@kismofer1]

nice work. mind is a 2014 5.3 6 speed does mind has the thermostat

[@joelcalvillo9487]

Nice video great details

[@rhasheedharrison9547]

So this procedure is only done when upgrading to an aftermarket transmission cooler?

[@CharlieAtkins]

No, it's done to any 2014 and up GM Silverado or Sierra 1500's 2500 and 3500's Don't have them...

[@donknicker8110]

Isn't it possible to just put the new updated thermostat in if your lines are not leaking

[@adamsnyder8019]

I had my transmission on a 2014 gmc with 5.3 go to 232 before it cooled down when I was pulling a trailer and a compact tractor on it and the transmission is new think this would help my transmission last longer

[@kurtlarson1151]

absolutely. 200F no good for long tranny life. Keep 150 ish or preferable even a little lower.

[@93gmctruck18]

I have a 2016 Cadillac CTS I’m trying to do a flush on the transmission, do you think this car has a thermostat on d transmission please help me out bro.

[@kurtlarson1151]

call your dealer with the last 8 digits of the vin number

[@davidchapman1986]

I think I may have the opposite problem. My transmission takes forever to warm up. I think my thermostat may be stuck open. Starting cold it'll read around 70-80F (close to ambient temp). Driving for 15 minutes 30-45 mph it'll have only crept up to 90-95F. Another 15-20F mins of driving under those conditions and it barely gets to 117-125F. It threw a P0711 (fluid sensor performance) which made me think it was just bad sensor but now I'm thinking it detected the difference between ambient/coolant warm up and transmission temp. Recently had coolant flush but I can't imagine I have an air bubble that hangs around the lower radiator hose to cause this.

[@mikekruger8806]

Is the transmission still running?

[@davidchapman1986]

@@mikekruger8806 They replaced the sensor and it was running when I sold it in November 2021.

[@eastsidee9435]

Can u do this while just taking the nut off and the clamp spring under the truck? I don’t wanna mess with all the lines lol

[@michaelcarson6744]

What's the part number on the flat piece that holds trans lines in the thermostat

[@andrewpeters87]

Do you know which line is the supply and which is return?

[@mike1590]

For anyone who has done this repair for the AWD version, could you shed some light on what components, if any, need to be removed to snake these lines out and then back in. Thanks!

[@genaroescamilla1745]

Hello I have a 2015 Yukon Xl SLT 5.3L do I need to delete the thermostat ?

[@kurtlarson1151]

If its a 6L80e transmission

[@andyschloesser2098]

Does the transmission fluid need to be drained before removing cooler line assembly?

[@AaronHinesAuto]

No sir!

[@teenice894]

I need new cooler lines because they're leaking I live in New England where it's typically cool. I don't do any towing or anyting could I use swap them out without deleting the thermostat

[@AaronHinesAuto]

Yes you can! New lines will come ready for you to install with thermostat

[@teenice894]

@@AaronHinesAuto thanks for the reply, went to the dealership today for the brake booster recall on my 16 Chevy Tahoe.. and they pointed out the leak in cooler lines for a whopping $400+ dollar repair. I do all my work myself but I love to turn to KZbin to see it done for tips + tricks... thanks for posting definitely a thumbs up!

[@mrrude86]

Does the 8l90e on my 16 5.3 have the same concept?

[@AaronHinesAuto]

Yes

[@captainhowdy1143]

Great video! would this process work on a 2012 GMC Sierra 1500 5.3 4wd?

[@AaronHinesAuto]

No, GM didn’t put thermostats in the transmission until 2014. Thank you!!

[@shaun8796]

Great help

[@familyguy5081]

The cap must be a paid actor because mine is seized up after removing that snap ring.

[@phoenixxarizonaa9629]

Do these things make noise like its clogged i swear thats where its comin from??

[@jd8651]

Did you ever do a video on the other two cooler lines that run towards the back of the drivers side?

[@AaronHinesAuto]

Those are oil cooler lines for the motor. Next time I replace those at work I’ll do a video!

[@jd8651]

one of mine are leaking at that crimp

[@jd8651]

@@AaronHinesAuto I just replaced my engine oil cooler lines and this video was perfect, and helped me very much. Thank you sir.

[@davidmarabella8441]

Where to find this for 2015 Extended cab with 6l80

[@rrandolph63]

is this a better way to delete the thermostat instead of your lest video on deleting them?

[@AaronHinesAuto]

It’s a quicker way yes. I’ve done both ways and they work just fine. However I have seen lower temps with the plug method on extreme applications, high ho, heaven tow etc.. but for just driving around town go with the flip method

[@kurtlarson1151]

@@AaronHinesAuto I suspect the really high temps you are seeing may be because the inverted valve plunger probably doesn't seal 100 %, where as the threaded pipe plug does. That 100% seal give a little better cooling, but for the effort, not worth it for most peeps.

[@circlepfarm9729]

That is a great video! How do I know which transmission I have? It’s a 2014 with a 5.3.

[@AaronHinesAuto]

6speed! 6l80e

[@AaronHinesAuto]

Thank you!

[@circlepfarm9729]

Thanks

[@ducktapeNglue.]

Thanks so much!!

[@aaronhuttsell8380]

Get Video! Helped alot.... Thanks

[@ngirardo86]

DO NOT DO EITHER OF THESE THERMOSTAT BYPASS PROCEDURES. Doing them this way also deletes your transmissions ability to bypass in the event a line becomes blocked or anything like that and you will RIP that trans. Buy a legit bypass kit from someone like superior solutions. Slows you to get rid of the thermostat AND keep the bypass. My Sierra with 44k runs normal at 127-133 degrees now. It’s wonderful.

[@sheawing2232]

So no need to by anything at all just flip the thing around and thats all?

[@kurtlarson1151]

yep

[@captainhowdy1143]

Thank you Man!

[@AaronHinesAuto]

you bet!

[@Smitty_0313]

This definitely isn't where the ATF Cooler lines go into a 2014 4.3L. Both of mine go into the radiator on the passenger side, one high one low. Both of the engine oil cooler lines go into the drivers side, one high one low.

[@larrydash7533]

Mine too, I have a 2014 Tahoe, which ever one he is working on looks to have an external transmission cooler. Have you changed your lines yet, I need but was curious how difficult it is with the transfer case and cross member present. Any input is appreciated 👍

[@Redsfanatic32]

I ran into this today, doing a thermostat job on a ‘15 tahoe. 14s and 15s still have the old style quick connect lines, however, per the TSB #21-NA-299, they now have a thermal bypass valve that opens at 158 degrees instead of 195. This valve uses the cooler line style that you’ve got here. It states if you have the old quick connect cooler lines you’ll have to purchase the updated lines as well, and I can’t find just cooler lines that’s separate from the bypass valve, with the updated style of affixing to the bypass valve itself. So I had to buy another bypass valve I won’t even use, just to get the updated non quick connect lines.

[@CharlieAtkins]

You do NOT need a thermostat on a transmission cooler period... You need to bypass the thermostat all together... 👍

[@Redsfanatic32]

@@CharlieAtkins extremely ignorant comment not taking into consideration the climate the vehicle is in. Where I live, if you don’t have some sort of system to help retain heat in your engine or transmission you will have operational issues and moisture issues within the case, as it’s frequently below freezing here. I tried running my truck without a thermostat and what that gave me was shorter fluid life, sluggish shifts, and awful TCC apply. A 160 degree thermostat is perfect because you can still warm the fluid up to where it’s viscosity is correct, and it doesn’t heat up too much like the old thermostats did.

[@CharlieAtkins]

Well I guess you are pretty ignorant by making a statement like that without knowing the facts... You ever wonder why 2500 and 3500's Don't have a thermostat on them at all... Because a transmission cooler thermostat was only put on 1500's for Fuel Economy standards... You need to do some research bro.. The poor TCC apply is caused by inferior TCC clutch disc lining material and GM's poor TCM programming... (Another case of GM CEO Mary Berra trying to save a cent and a half) Fluid should be replaced every 25-30k on these trucks... A 6L80E or a 6L90E transmission should NEVER be flushed... Just drain and fill.. Now on the other hand a 8L90E can be flushed and in fact there is a GM TSB for a updated fluid flush procedure for the 8 speeds... 👍

[@j.d.7321]

If this procedure eliminates the function of the thermostat then why reinstall the spring and plunger back into the housing, I would think that will just restrict flow.

[@CharlieAtkins]

If you leave the thermostatic valve out altogether it won't direct it to the cooler guy... 😳

[@kurtlarson1151]

yes you want to restrict flow 100% (to the bypass that is), you want oil to be directed to the cooller.

[@kurtlarson1151]

@@CharlieAtkins correct

[@daltontallman8721]

I Am 99% sure my 2015 Silverado doesn't have a Transmission Cooler ... Anybody know why that would be??

[@vitaliymelnychuk3776]

I dont understand why cant you just throw the thermostat away and install the cap..? The cooler empty inside, oil circulates.

[@AaronHinesAuto]

The oil will not recirculate to the cooler. The block is nothing but a void with sending the fluid two directions. Back into the transmission or to the cooler. Taking out the thermostat will not direct flow to the coolers

[@kurtlarson1151]

like aaron hines said, with no mechanisms inside to direct the flow, the oil will just flow back into the transmission. A little oil might go to the cooler simply because the reverded valve may not seal as well as the OEM way.. simply check your temperature and that will tell all..

[@Byronwi]

im not convinced this is going to work w the thermostat upside down

[@kurtlarson1151]

have you tried it. If not do it, and just watch your tranny temps. Not rocket science. Upside down it should seal "most" of the oil from recirculating and bypassing the cooler. Not a perfect seal like the drill and tap but 10 times easier, reversible, and should provide 95% of the cooling the drill and plug will do.

[@bogey19018]

Why even put that stuff back in, why not just the cap?

[@kurtlarson1151]

It will just recirc directily back into the tranny without going thur the cooler.

[@Thunderroad8517]

The 2019 model is not so easy. What a piece of stupid engineering! The lines wrap around to the front of the radiator. 4.5 hrs. Really!!! And to top it all off the truck is covered with dried mud. Sorry for my rant. You did a great job with the video . Thanks

[@crbrepairmotorcycles6608]

Clips are a nightmare to put back on

[@TheJcrandazzo]

Dont want to delete a thermostat.. Not a good idea.. In cold weather a cold transmission will be sluggish and cause delayed shifts and damage down the road.

[@longrange1114]

depends on where you live. I did the " Flip" method he describes here and lowered my trans temps from 200 down to 155 degrees. I am in Texas and for 90% of the year it is warm here. On the colder days, the trans will still warm up just fine. If I lived in Alberta, Canada tho, I might not have done this upgrade.

[@Anonymous01416]

Why not just remove the whole internal out and put the cap and retainer clip back?

[@AaronHinesAuto]

With that, fluid would constantly be bypassing the cooler

[@kurtlarson1151]

Think about what would happen???

[@billysanford9799]

Why in the name of heaven are you messing with the lines? Doesn't GM sell just the thermostat and housing by itself?

[@Jorge.Rangel]

I guess you didn't pay attention. He shows where the line was leaking, the reason why he's changing the lines and while he's at it flipping the pill.

[@zacharycrawfski2276]

Transmission is shot that fluid was black and burnt

[@TheAmericanUhate]

Damn chevy junk

[@josh_9266]

Will this work on a 2020 with an 8speed auto ?

[@AquaGuardPoolAlarm]

Does the Allison duramax 2008 have a thermostat as well

[@randylee2549]

Let's worry more on our trucks did gm figure out on lines that do not leak

[@gmpartsguy9614]

No. First time GM trucks started using a trans cooler thermostat was the 2014 1/2 tons with 6L80.