New TBV for 6L80

KyleC4

Tech
Dec 30, 2016
470
48
28
Bay Area
Hey guys

just letting you know for any of you that do own a 2014-2020 Silverado/Sierra/Yukon/Tahoe with a 6L80 (MYC) transmission, there is a new thermal bypass valve available for them. It lowers the opening temp of the valve to 158 when it’s fully open vs previous design 190. They are wanting us to install these anytime during a rebuild or even for a customer concern of any kind. Even if we can’t duplicate it. So that tells me their engineers think these lower trans temps will help.

Part Numbers
86774933 Thermal Bypass Valve
23135703 Seal (between tbv and converter housing)
 

Mike L.

Got Sheep?
Staff member
Vendor/Sponsor
Aug 12, 2006
15,686
232
63
Fullerton CA
You’re fine there. GM didn’t have a thermal bypass valve on those years. There is just a small aluminum block that secures both trans cooler lines coming into bell housing.
When you get a chance Monday, give me a call at the shop.