6L80 Troubleshooting PT3 - Hydraulics: Valve Body and Pump Stator Support

I continue the General Motors 6L diagnosis and troubleshooting series with a deep dive into the valve body and pump stator support (aka pump cover) including an overview of the valve body and role that it plays in the function of the transmission, common drivability symptoms associated with the valve body and a comprehensive vacuum test of the upper and lower assemblies.
I also explore the pump cover and associated hydraulic circuitry, performing a vacuum test of the four hydraulic circuits located in the cover and show what a worn pressure regulator valve looks like.

[@larryschaum6280]

Ok, I am in the middle of watching this. I would like to ask what CFM your vacuum pump is. And if you don’t mind. What brand.

[@nickstransmissions]

Hi Larry, not sure on the brand or CFM as I bought that pump years ago but any decent air pump should work fine with the vacuum tester.

[@mishutkin101]

I've got some noise coming from transmission area where the torque converter is. Any clue why it does that? kzbin.infoWIF1Gf_yZQA?si=HZ5noulPx-y8JpuK

[@nickstransmissions]

Hi Mishutkin, thanks for watching...Your link isn't working; I suspect you posted the YT Studio link instead of the public-facing link but no worries, it's very difficult to diagnose noises via video anyway. I'd plug in a scan tool to see if you notice anything unusual in the transmission and torque converter live data streams; perhaps do a pressure test as well to see if your pressures are below normal or erratic; if so, the noise is likely the pump rotor/slide breaking up or fractured into two-three large pieces. You can also unbolt the the torque converter from the flex plate, spin it through the inspection cover to see if the noises are present...If not and there's no hint of anything unusual, then it may be either engine or external to the engine/transmission.

[@mishutkin101]

Thank you for your reply Nick. Sucks that the link isn't working. Do you have any other social media? So the noise is coming from the transmission area when the car is in park or neutral. It's not a grinding noise but more like a fuel pump noise. To me it sounds like it's coming from the torque converter. I've taken my truck to a transmission shop but they said transmission is fine(don't know if I trust them) Also I've got a innova 5610 scan tool and there's no codes. I tired doing live transmission data but I know nothing about it.

[@nickstransmissions]

It could be coming from the converter as those JMBX converters fail frequently...If it is converter, you could be hearing torrington bearing noise...There's three bearings in that converter and if it begins to fail, one or more of them may be going bad. I would undo the bolts to the flex plate and spin it to see if you can still hear noises coming from the converter...If so, I'd remove the transmission and replace the converter...I'd also take the pan off the transmission to see if any burnt clutch material or metal, etc is at the bottom...

[@66and72nova1]

Where are you located? Your not in Los Banos California? Just called them.

[@nickstransmissions]

@@66and72nova1 Are you asking me or Mishutkin101? If you're asking me, why do/did you think I'm in Los Banos?