⇒ The Transmission Cooler Bypass Valve (TBV) should be replaced with a new (TBV) that has cooler operating temperature and should be replaced when any transmission repair is performed including Customer Concern Not Duplicated (CCND). Note: The “70” may be difficult to read as a dot print maybe stamped over the “70”.

2021年9月27日 · The Transmission Cooler Bypass Valve (TBV) should be replaced with a new (TBV) that has cooler operating temperature and should be replaced when any transmission repair is performed including Customer Concern Not Duplicated (CCND). The "70" may be difficult to read as a dot print maybe stamped over the "70".

2024年3月27日 · Item:Valve Assembly, Thermal Bypass TBV. Compatiable with:Fit for 14-20 Cadillac Chevrolet GMC. Material:High-quality Aluminum. Replace part number:86774933，13511136，85585333. The purpose of the thermal bypass valve (TBV) is to bring the transmission fluid up to temperature quickly.

2020年8月23日 · A better upgrade is replacing the factory 190°F thermal bypass valve, TBV, with the new available lower temp 158°F TBV instead of modifying the 190°F thermostat. TBV Part Number 86774933, stamped with “70”

Replacing the Thermal Bypass Valve (thermostat) on GM 6L80 Transmission referencing TSB 21-NA-199. This Silverado went from running around 190 F to 145 F!!!...

2022年2月21日 · The TBV is basically a thermostat for the transmission, when the fluid temperature reaches x, the valve opens and allows coolant to flow through the transmission cooler. The original TBV that was used on almost all GM vehicles with 6L80, 6L90, opened at 194 degrees, and is mounted directly on the transmission.

2021年10月5日 · They are supposed to open up at 194⁰ to allow for cooler flow to cool the fluid. My suspicion was that it was either not opening at all, or was opening too late, with the not opening at all being the more likely one due to how hot it's getting. I did notice a TSB on my scan tool that was very new. And it directly relates to this issue.

The new TBV only needs to be replaced once. The new valve has a 70 stamped into the bottom of the valve. The “70” stamp is visible on the valve when installed on the transmission. The revised TBV has a full open temperature of 158f (70c). The previous TBV had a full open temperature of 194f (90c).

2012年10月1日 · It is being replaced with a GM remanufactured 6L80 next week. I was doing some reading last night and discovered the issue with the TBV. Some people have suggested “flipping the pill” but it also looks like GM may have fixed the issue on newer models with an updated thermostat for the transmission.

2024年4月18日 · GM Reman 6L80 Transmission - new TBV? Thermostat (and oil life?) Own a 2014 Tahoe LTZ with the 5.3 engine and 6L80E transmission. This is a recent purchase at 125k miles. Vehicle runs great but wish to keep it that way as...