TH350 valve body for 1969-1986, OEM and ready to install. Ships fast from the USA.
A 1969-1986 Chevrolet, GMC, Pontiac, Oldsmobile or Buick running a TH350 behind a bracket or drag car doesn't want the transmission deciding when to shift - it wants the driver deciding, every time, on the same gear every run. This is an OEM-pattern casting (321100) converted to a full manual, reverse-pattern valve body: it removes the TV cable and governor's automatic shift logic entirely and swaps the shift gate order so reverse sits away from the forward gears.
A stock TH350 valve body times every upshift and downshift off throttle position and road speed through the TV cable and governor. A full manual valve body removes that logic from the equation - the transmission only changes gear when the shifter is physically moved into the next position, so every launch and every shift point is exactly where the driver puts it instead of where line pressure and governor weight happen to land that run. The "reverse pattern" part moves reverse out of the normal shift path, so a shifter that gets bumped or overshot under hard acceleration can't drop the car into neutral or reverse at speed - the forward gears are grouped together and isolated from reverse.
If the transmission is still shifting through the TV cable and governor and the complaint is harsh or inconsistent shifts, start with our TH350 valve body problems and testing guide to rule out a simple governor or modulator fix before committing to a full manual conversion - a manual valve body is the right call once you want shift-point control, not a repair for a single bad shift.
This casting fits the TH350 across the 1969-1986 production run, but confirm your current valve body's casting number and bolt pattern against 321100 before ordering, and make sure your shifter can run a full manual, reverse-pattern gate - a standard PRND21 column or console shifter is not set up for this pattern and will need to be swapped for a race-style slider or ratchet shifter. See the full TH350 parts collection for the automatic-pattern versions of this valve body if you want to keep stock shift logic.
Drop the pan and change the filter while the valve body is out so debris from the old unit doesn't circulate through the new one, and torque the case bolts in sequence to spec. Because launch and drag use loads the clutch packs harder than street driving, pair this with a fresh clutch drum and sprag clutch if the originals have any track time on them, reseal the case with a metal-clad external reseal kit while everything is apart, and add a transmission cooler if the car doesn't already run one - repeated hard launches generate more heat than a factory cooling setup was built for.
| Transmission | TH350 |
| Year Range | 1969-1986 |
| Condition | Remanufactured / updated |
| Shipping | Ships from the USA |
Doing this repair right usually means replacing these at the same time. Same transmission, ships together.
It removes the TV cable and governor's automatic shift logic. The transmission only shifts when the shifter is moved into the next gear, so the driver controls every shift point instead of line pressure and governor weight deciding it.
The shift gate order is changed so reverse sits away from the forward gears. If the shifter is bumped or overshot under hard acceleration, it can't drop into neutral or reverse the way it could on a standard forward pattern.
No. A full manual, reverse-pattern valve body needs a race-style slider or ratchet shifter set up for that gate pattern. A stock PRND21 shifter is not compatible.
It's built on the 321100 casting used across that range, but confirm your current valve body's casting number and bolt pattern before ordering since the TH350 went through several updates over its production run.
If the clutch packs and sprag have any track time on them, replace those at the same time, reseal the case while it's apart, and make sure the car has a transmission cooler sized for repeated hard launches.
No - a full manual valve body does not use the TV cable or governor for shift timing. Those automatic shift control components are removed from the equation entirely.
