Vacuum control valve for the TH350 or 400

[Robyn]

Many folks ask about installing a TH400 or even a 350 behind a 6.2 or 6.5 that had an electronic box before.
The trannies will usually swap in fine with minor things such as the flex plate to deal with and maybe an adapter for the input shaft or the center mount.

All the vacuum modulated trannies require a **control valve** that bolts to the injector pump to control the amount and timing of the vacuum to the modulator. (Must have a good working vacuum pump either the rear mounted one or a belt driven one) :)

** The GM part number for this little creature is 14057219 andf can be ordered from your favorite GM store.** :)

Many countermen/women :D dont have a clue about this little valve or even what you are talking about when you ask.

This valve will work to run either a TH350 or TH 400 box with the 6.2/6.5 diesel.

Robyn

[Dave Brooks]

Do you have a diagram of how the vaccum lines are run. I need one because the previous owner of my truck had messed them up and they need to be re routed.

[Robyn]

Line comes from the vacuum pump to the valve and the other side of the valve to the modulator on the tranny.

If you connect the lines to the valve wrong it will not work, just swap them.

Install lines, start engine and check vacuum at the modulator.
High vacuum means you got it right.

The vacuum should decrease as the throttle is opened (simulates the response of a gas engine under load.


Missy

[62fan]

82 models: Outboard nipple goes to transmission, Inboard nipple goes to vacuum pump.

83-87 models: Top nipple goes to transmission, Bottom nipple goes to vacuum pump.

Not sure if there is a difference in later years.