PabloB19

I have a 77 C4 transmission that I recently rebuilt. I have the transmission back in the car and now the car will not shift out of 1st. The modulator holds pressure good, the hose to the modulator holds pressure, and the pin and valve for the modulator are installed correctly. I rechecked my work twice now on the shift kit that I installed on the valve body. My pressures at the transmission are P,N,D 60psi. Reverse is 180psi, 2nd and 1st 120psi. Fluid looks good and clean. Governor is clean and functional. I air checked the bands and they are adjusted correctly, 10inlbs back off 1 1/2 turns for front band and 2 turns for rear.

I am starting to think that i may have the governor installed backwards but I can't find a picture that shows a correct install. I don't want to have to remove the tail shaft any more than I have to. The car has been down for a month now and it is my only car, please help!!!!!

MonsterBilly

This may be a silly question but have you checked the linkage? Maybe its a little out of wack.

jojobanks

have you tried going from 1st to 2nd to drive? Does that shift properly?

I just got done rebuilding my trans about 2 months ago and when I adjusted the bands I put them both at 1 1/2 turns backed out.

If you installed your governor backwards then you have to at the very least drop the driveshaft back out. You may not have to drop the crossmember to take off the tail shaft.

PabloB19

The gas pedal linkage is off, I noticed that the bracket holding it on was loose so i tightened it and now it feels totally different. Do you think that could cause it?

It will not shift out of first manually or automatic.

Does anyone have a picture or can explain how to properly install the governor? As in which side is which.

PaulS

As long as you have 10 or more inches of vacuum at the modulator it should be good. The spec for the rear band is back it out three turns - that may be part of your problem but I think you have the governor on backwards. That would keep it from shifting.
Does reverse work ok?

Paul

JMD

Some of the aftermarket ADJUSTABLE modulators often require adjustment out of the box for the transmission to shift.

Not sure about the C-4 setup, but the GM THM 350 adjustable modulators had an adjustment screw inside the vacuum connection nipple. Might check that before pulling the transmission back out....

jojobanks

The governor is pretty simple. If you think it's wrong just flip it over. Look at the Passageways inside when you unscrew it and line them up.

I'm with JMD though. I would try adjusting the modulator before you go after the governor. if you take the hose off and can twist the center piece with a screwdriver then your is adjustable. I know mine is.

PabloB19

Fixed it. I took the valve body back out and noticed the 1-2 and 2-3 shift valves were stuck. cleaned them all up real good and the car shifts great now. Just need to adjust kick down and I'm good. Thanks for the help.