727 No forward or reverse

I wanted to go on with this thread, not to start new one.
In my case I was accelerating slowly and suddenly car acted like it went out of gear, I could press gas pedal without any effect.

I have 727 with manual vb and Hurst shifter. Transmission goes into park and neutral, when I put it in gear and press gas pedal car moves forward a little but not enough to drive.
Also nss works, I can only start the car in Park and Neutrak
All forward and reverse gears dont work and it acts the same on every gear.
Any tips? I will probably take the trans off the car next weekend. Can it be damaged torque converter?