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Hey everyone. Got a real head scratcher. Can't figure out what else to replace.
Got a 96 F350 with a 7.3l and E4OD.
Story behind it;
Just did a full engine swap and transmission swap from a donor truck that ran perfect, shifted beautifully. Only reason I made it a donor is because the front frame was slightly bent and I need a dually (which is my current truck I swapped everything into.)
After I was finished swapping everything out, cranked on, and drove it, didn't shift past 2nd. Reverse, 1st, and 2nd shift fine. Strong.
I've swapped the transmission harness, PCM, VSS, TPS, MLPS, PCM relays, PCM diode, no fuses blown, all relays new, new batteries, and a new alternator.
Well both shift solenoids need to function for the transmission to shift into 1st while in "D".
More than likely it's a stuck shift solenoid or hydraulic fault with the valvebody. Especially if you were banging the transmission around swapping it.
If you're good with wiring, you'll want to tap a test light onto the shift solenoid wires down at the transmission and monitor them.
If you're not comfortable with wiring and tapping into wires, I'd start by dropping the pan and inspecting the solenoid pack.
They guy we bought it from had bought it after the truck sat for a few years. Full of atf. He was driving it for a few hundred miles before we bought it off of him. He sold it because he was moving out of the country and couldn't take it with him.
Solenoid pack is plugged in. Fluid level might be a bit high though. I'll check in a little bit. How badly can that throw everything off?
I still do have the old transmission. What had happened was that the original transmission had just been rebuilt and didn't have but a few hundred miles on it when we bought it. It started blinking the OD light, slipping and shuddering, but the weird part was that all the symptoms came and went. Some weeks it ran like a scalded ape, some weeks like a ran over dog limping home. Ended up blowing out the front main seal and burning out clutches, busted the pump and pieces of the TC in the pan.
The donor truck ran beautifully. Didn't slip, no shudder, no OD light blinking, just strong and nice shifts in all gears.
What I'd personally do first is hook up two testlights to the shift solenoid wires, and verify the computer is commanding the transmission to shift gears.
The computer turns the solenoids on by grounding them, so you'd want to connect the other end of the testlights to battery positive.
If the computer is indeed commanding the solenoids, there is an internal fault with the transmission and I'd first start by trying to swap the solenoid pack from your old one - after cleaning it thoroughly.
That's of course assuming all fluid levels, etc.. are good.
Tested the tcc solenoid and grounded it out. Stalls engine when in drive and brake on. So itd be safe to say that works.
Does anyone have the diagram to the 96 7.3 pcm harness? I'm wanting to bypass the whole harness and add a wire from the pcm to the transmission. Thinking somewhere in the harness it's gone. Figured this would be the easiest route.
Is there anything inside the cab, specifically the column, that'll make the transmission not shift right?
I've tested the solenoid pack and everything is cherry, the wiring harness all the way from the pack to the PCM is solid, and all connections are good. Anything else I'm missing?
