What will fit my 88 d50

I have already do that that with no luck. It's why I'm trying to figure out what will fit the transmission. Preferably something out of another vehicle trying to go the cheapest route possible not because I want to but because I'm broke. Hoping there's something out there for another vehicle. Direct fit my automatic transmission.

These had the Mitsubishi motors in them, 2.0 & 2.6, either with a 3-speed, the 2.6 could also be had with a 4-speed. AFAIK these motors are extremely common, they were in similar vintage Mitsubishi models (like Lancers) and even in Saturns. You will just have to hunt one down, call up local mechanics, they may have some laying around, or hit up all the bone yards. I know in the north bone yards tend not to hang onto older cars so finding anything from the late 80's may be a stretch but you never know. You really need to get the numbers from your engine and tranny so you know exactly what you got. If this truck is low mileage, I would be more inclined to fix the current engine, cuz swapping it out can open a can of worms if you can't find something that is 100% compatible.

These trucks actually had what is called a baby 904 3 speed auto and a KM145 5 speed, the 4 speed was an older offering. there is also a 4 speed auto, not to be confused with the manual. as long as you get the wiring harness and ecu for your engine, you should be fine. i am doing a 82 2.6 swap into a 87 with a electronic carb 2.6

you can find a KM132 or a KM145 pretty much anywhere and for dirt cheap.