8L90 Thermal Bypass / Thermostat mod. Active bypass STL010

[Tech89]

Hey guys, I did the thermal bypass conversion to active by pass on my 2018 8L90. Did a step by step video because I hadn’t seen anybody do an actual full replacement video nor had I seen one on a 8 speed. Trans runs about 45 degrees cooler now. Check it out and let me know what you think. It’s the exact same procedure on 6 speeds just mounts different on the transmission.

 

[UofAZCats]

Great video.  I have that same kit and have been planning to do this for some time.  This is the best video I have seen on the install.  Good work.

[CamGTP]

You don't even need to buy anything if you really wanted. Just flip that pill around and slap it back together, works like a charm. The 6 speed video on youtube shows that way.

 

The visual on the how to get to it and remove it surely helpful though for people wondering about it.

[Tech89]

I live in Iowa. It gets -55 degrees here. Not an option, the STL010 works off viscosity and will go back into bypass mode if your cooler were to be restricted, blocked/frozen or simply the fluid isn’t thin enough yet.

[Grumpy Bear]

Nice job all the way around.

Keep the videos coming!

[CamGTP]

Minnesota gets colder than Iowa, trust me I live here. No thermostat is just fine here.

[Tech89]

8 minutes ago, CamGTP said:

Minnesota gets colder than Iowa, trust me I live here. No thermostat is just fine here.

I feel a d*** measuring contest coming. So on that note, I’m not rich by any means but $42 is not financially crippling to me. The video is to help people, who have asked, do the install of the STL010 correctly. It helps prevent damage to the transmission if freeze up or blockage occurs that a pellet flip does not. Cheap insurance. SKOL

[TomRen7]

So SHIFT Tech- is a delete kit,  Does GM#86774933 valve do the same thing? Or is -933 valve not for 8sp Trans?

  -933 valve does not GM parts search as application for my ,'17 6.2 8sp...while blogs include 8s and Techdoc# 5898242 includes 8sp...? Confused

[TomRen7]

9 minutes ago, TomRen7 said:

So SHIFT Tech- is a delete kit,  Does GM#86774933 valve do the same thing? Or is -933 valve not for 8sp Trans?

  -933 valve does not GM parts search as application for my ,'17 6.2 8sp...while blogs include 8s and Techdoc# 5898242 includes 8sp...? Confused

  If the 158* -933 valve , is for 8sp's too, Which 50$ purchase is best?

Replace valve or SHIFT delete kit?

 

[TomRen7]

Info..Does it matter if 6.2 8sp has TOW option...? 

[GENE SEWELL]

INVALUABLE IN FORMATION .IN CANADA DEXTRON HP OIL EXSPENSIVE HARD TO GET .AMS OIL SIGNITURE SYNTHETIC CHEAPER EASY TO GET . THE TF922 FILTER CROSSES OVER TO A 24295812 <AC DELCO NUMBER .  FOR TRANMISSION FILTER CHANGE AND 8 QUARTS OF OIL WITH BLOWING OUT COOLER LINES :[ACUALLY JUST UNDER 8 QUARTS/LITERS ]

THE KIT IS AWSOME BY THERMOL BY PASS IS A EXSPENSIVE FAILURE AND THIS IS A ECONOMICAL FIX FOR THE HANDY GUY .  THANKS .

[AZJim]

If my truck doesn't have a TBV just a block and 2 lines going into the tranny is there a modification that is available to install a TBV? Trans gets very hot whentowing. Any help at is appreciated

[CamGTP]

4 hours ago, AZJim said:

If my truck doesn't have a TBV just a block and 2 lines going into the tranny is there a modification that is available to install a TBV? Trans gets very hot whentowing. Any help at is appreciated

Installing a thermostat would just make it run hotter. You have internal transmission problems if it always gets hot while towing. That or your transmission cooler is plugged up, which would also tell you that the transmission is in need of repair.

[DHBWA]

Didn’t see where anyone responded on the question if the later 6 speed 70c TBV (85584365) will fit the 2019/2020 8 speed? I would do the bypass by just threading and plugging the hole between the ports but I still have warranty….Another option is buy the whole TBV and just swap the internal pill…..

?????

[Grumpy Bear]

Yes, the pill will work. 

Edited August 15, 2023 by Grumpy Bear