B2300 5spd automatic transmission is slipping

I'm new to the forum and am seeking help. I've searched around some, but haven't yet found the correct thread for advise.
My '06 started slipping the other day in drive (O/D) and in reverse. Now it won't move at all in reverse, except a slight motion when I put it into gear. It won't move from a start with the selector in drive, but would maintain speed if I am already going over ~30MPH.
I have to put the selector into 2nd or 1st to get the truck to move, at which time it runs fine. Once at speed I can move the selector to drive and it will keep going OK.
A friend with a OBD reader says there aren't any engine or drivetrain error readings, except the O/D switch it beyond "self calibration" range.
The O/D light sometimes blinks on the dash, but still didn't cause an error code.
The tranny has about 143K on it and the oil is at the right level.
Any suggestions?
Thanks for the help.

Where you from?

It may have overheated, hate to say it but you are probably looking at a rebuild.

That was gonna be my post but I wanted to look up local wrecking yards for him.

Time for motor swap. Get that Ford motor and trans out, and put in something reliable. Like a skyline motor.

That, or I recently came across a company that makes a bolt in kit for the Mustang 5.0!

but imagine the fun of a rb26 turbo under the hood of a newer b series (ranger) i've seen small blocks in rangers, but not a skyline motor. i have seen skyline motors in the older body style mazdas, but still, thats not the newer body style.

Yeah. I love the sound of turbo over v8 any day. I was just thinking of simplicity since there is a bolt in kit lol