TH350C Valve Body Disassembly

I disassemble a TH350C valve body.
Note - the only difference between a TH350 and TH350C (lock-up converter) is the governor pressure switch port in the valve body casting. All of the valve trains are otherwise identical between the two valve bodies.

[@joshuadeats6768]

Excellent video easy to follow and great learning thanks

[@lad63bird]

I have a question about my 1981 c3 corvette with a TH350C trans? I have done away with any sign of the ecm and accompanying peripherals, I.E. ELECTRONIC CARB, ELECTRONIC DISTRIBUTOR AND ALL THE EMISSION CRAP, . l left in trans that has lock up without the computer. I have a two wire connection to the trans, one is 12 volts hot with a brake switch in line to cut off the power to the trans on braking and another wire that comes from the ecm PIN P, BUT ECM h is no longer in car. My homework says this 2nd wire from the ecm is a ground that is closed circuit when the engine temp and the egr tell the converter the car is sufficiently warmed to engage lock up. So does this mean that now that I have installed a port vacuum operated TCC LOCKUP switch that sends 12 volts to the LOCKUP solenoid that all I need to do to make it work is send a constant ground on the other wire hat goes to the solenoid in the trans and just let the vacuum/brake switch, and pressure switch determine when to engage the lock up and when to disengage it? YOUR EXPERTISE WOULD BE WELCOMED!

[@nickstransmissions]

That sounds correct and is basically how many internal/external lock up kits for the TH350C and other transmissions of that era (700r4, 200-4r, AOD, etc) work but admittedly, I don't have any hands-on experience installing those kits or any of the various improvised/alternative methods folks use to keep the converter clutch working when deleting the PCM and electronic engine management components in 70s and 80s vehicles.

[@djmrvip]

Hey Nick my rebuild kit came with new valve body gaskets (that I needed since my old ones was broken when removing) Question is I have a transgo shift kit is it okay to use that rebuild gasket that’s not from them? Thanks you know I got you on more coffees

[@nickstransmissions]

What Transgo shift kit? If the basic kit (SKTH350) then use the gasket set that came in your main rebuild kit. The non-lock up gasket sets do not have the tear drop shape toward the front of the gasket - this tear drop is for the TCC check ball. So if your TH350 is a non-lock up, use the gasket set that lacks that tear drop cut-out.

[@djmrvip]

@@nickstransmissions okay there was like 6 gaskets in my big rebuild kit from transtar. Is there anything you have to do the gaskets to adapt to the dual feed upgrade I also did thanks to your other video. Think I’m almost done once I figure out this valve body gasket thanks to your videos 🙏

[@nickstransmissions]

Use the gasket set that does not have the tear drop shape cut-out for the TCC check ball location on the case...It's roughly at the 12 oclock postion, just before the front pan rail. The VB to plate gasket for the non-lock up also has a roughly 'S' shaped channel toward the top that follows the contours of the thick metal hold down plate. That gasket is not used on the TH350Cs.