46rh troubleshooting a rushed 2-3 shift on fresh rebuild.

dpaqu

New member
'93 D250
I've rebuilt the trans with:

-5 pinion planetary and corresponding intermediate shaft,
-new steels+ clutches
-billet apply lever and servos ECT.
-TFOD-Hd2 valve body
-tighter Goerend converter.

Truck is in OD by 35mph. Rushes the 2-3 shift and won't hold second gear when "2" is selected. Going from "2" to "D" engages the OD. 1-2 shift feels good. Holds first gear pretty well depending on were I put the TV cable. Sometimes downshifts after I've come to a stop making me think I have a mushroomed governor valve. So I've done some pressure readings.

I’m getting the following pressures
-----------------------------Front Servo-----Rear Servo--------Acum. Port
Throttle valve--------------Front---Rear----Front----Rear----Front----Rear
Manual 1st gear-----------0---------0--------75-------110------75--------110
Manual 2nd gear----------0---------0---------0---------0--------75---------105
Drive-----------------------90--------125-----0---------0---------90--------125
Reverse -------------------20--------20---------------------------------------------
Neutral---------------------75--------75---------------------------------------------

The gov pressure is running about 1.7-1.9 x the MPH or about 60 psi @ 30mph with the throttle valve off (front) didn’t test it with it forward. This is double what the FSM recommends but maybe the transgo kit changes that?

Before I drop the pan and change out what is probably a sticking mushroomed gov piston (thanks to Guitar Jones from the moparts.org for that tip) I was hoping I might narrow down some other possible problems. Like I said earlier, it is rushing 2nd gear and going to 3rd real quick and doesn’t like downshifting. Shifts are pretty soft also. I didn’t drill out the shift hardness hole much on the transgo kit to help ease the shock loads on the driveline, but I didn’t think it would be this soft.
 
Why did you use the HD2 and not the TFOD-Diesel?

I wanted to have softer shifts to preserve the stock input and output shafts but still have high line pressure to hold the torque. It doesn't have a locking torque converter so this may have been overkill. From my understanding the TFOD doesn't have the option to drill out certain holes in the separator plate? I'm sure if your more knowledgeable you could get the stock stuff to do what you wanted.
 
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