I have a 2000 Dodge 2500 van, 5.2L w/OD transmission.
Having problems! Hoping this is the place to find some answers!

1) will this truck's transmission ID be a 44RE or the 46RE?
2) is the PCM and TCM integral, or separate?
3) If separate, where is the TCM located?

History- bought used 10 years ago, 60,000 miles.
Transmission suddenly leaked fluid everywhere @ 100,000 miles/ 4 years ago.
Professionally rebuilt. Cost-$1500.
Current mileage- 149,000.

Numerous problems;
1) 2 months ago, suddenly developed a driveline vibration... Intermittent, 40-70 mph, when under light accelerator. Releasing accelerator/reapplying accelerator will make it go away. Sometimes will return again, sometimes not. Had ujoints checked by 3 shops, the last removed and inspected the shaft. No fault found. Problem still exists.

2) Has always slip shifted 1-2 and 2-3, even before overhaul. Never slips once gear is engaged.

3) has always shifted "stupidly". Meaning, seems like it shifts to high too soon, then downshifts, then back to high. Makes me say out loud, "Please find a gear and make up your mind..."

4) 2 weeks ago, will shift through all gears fine for the first 20 miles, then refuses to upshift. I have to manually change gearshift to "2" from "D", then back to "D". Then it will shift. Accelerator manipulation does nothing to make it shift. Today, i drove 20 miles, went from 1st to 4th fine 4 different times. Then, suddenly refused to shift. Required gearshift manipulation. I stopped for 10 minutes. Restarted van, shifted perfect for another 4 cycles, then refused to shift again. I pulled over, put it in park, turned it off, cycled the ignition key 3 times, then restarted, shifted fine for another several times, then refused to shift again.
Up until this point, it has always downshifted to 1st gear right at stops, every time. Now, it has stopped doing that, and gearshift manipulation is once again required. Aaarrrggghhh!

So... Does this sound like a mechanical issue ( overhaul/torque converter time) or an electrical component failure? I've read many places that say the PWM Solenoid and Pressure Sensor are typical problems.

Transmission has not been serviced since overhaul, but fluid level is checked every 3000 miles when oil change service is done. Fluid level is right.

I have had to replace the PCM 3 years ago. Engine kept stalling at that time. No problems like that since.

I have NO check engine light... Ever. Code readers come up with "no codes found."
I welcome all suggestions and advice! This is my only work truck. If it goes down, my business is down.
Thanks!