So i have a 97 chevy 3/4 with a 4l80e that came with a 6.5diesel.... that motor unforunatly blew up and i currently have a cummins 4bt non-electronic motor swapped in... the entire swap is done but am having problems making the trans work. it is currently stuck in 2nd gear safe mode. I know there are controllers but they are a grand or more... all the wires are still hooked up but I believe it is missing some signals since the electronics from the motor are no longer there... I found a couple wiring diagrams but they are pretty complex. Here's the ??? I found the pins on the trans connector that give it power, as well as the ones for shift solinoid 1-2, 3-4, and the TCC lockup. could i hook these straight to switches? run the power to the ign, and switches to the solenoids? I believe i just need to hit sol 1-2 with juice for 1st, nothing for 2nd, sol 3-4 for third and both for 4th. or is the tcc solenoid the 4l80s 4th? I found this confusing... thanks in advance

p.s. my other option is to make the factory controller work but i dont know much about the 97 6.5/4l80e combo... I know the system needs the TPS so i would have to make that work on the cummins somehow. would the input and output sensors signals still be getting to where they need to go??? Brake light switch should still be hooked up... whats a manifold pressure switch and is it important to the shifts???? any help here would be awesome...

You could actually hit the juice to shift the 1-2 and the 2-3. the problem lies in controlling the pressure. The pressure is controlled by the pressure control solenoid.

To convert to manual
Transgo sells a conversion kit. You will have to install a vacuum fitting into the case and a vacuum modulator. The vacuum modulator replaces the pressure control soleniod.
I am sure transgo probably sells a full conversion kit totally bypassing the solenoids.

These photos are pictures of the vacuum modulator and fitting that was drilled into the case. Photos used with permission

Transgo will tell you to shorten the length if you are shifting too hard. Where the modulator is fitted in is where the pressure control soleniod came out.

So could a person also control the pressure control solenoid by switches? I see a force motor low and high wires and believe these control line pressure... are these simpley on off? do you only need high line pressure if you are under heavy load?? if so couldnt you just leave the pressure low until you wanted to put some power down???

Doesn't quite work that way. Computerized. The computer knows the viscosity of the fluid. If the fluid is cold the pressure is higher. Hot the pressure is lower. Let me give you an example. Your engine oil pressure gauge. Your pressure is higher when you first start it up right?
The transmission was designed to be protected through programmed algorithims. You simply can't risk controlling the amperage flow over the long run. You can get away with it but you will starve pistons, seals, burn clutches.
You have to install a vacuum governor as described in the pics.
Controlling the solenoids is possible. You can even (paddle shift) on the cheap especially if you have a vacuum modulator hooked up and no pressure control solenoid. :)

Search in the 6.5 section for teh DB2 pump conversion info. You could get a tone wheel on the balancer to provide 4 pulses per engine revolution for an RPM signal to the PCM, hook up the coolant temp sensor as well, and then give it a TPS signal and most likely it will shift.

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