1994 Plymouth Voyager A604 trans jerks badly when putting I

Transmission problem
1994 Plymouth Voyager 6 cyl Front Wheel Drive Automatic 279K miles

Greetings,

I have a 1994 3.3L A604 Voyager that has suddenly developed a terrible jerking when engaging the transmission.

The tranny was due for its annual service, and I changed the fluid(+4) and filter as usual.
I also changed the starter solenoid contacts at the same time, so I disconnected the battery.

Started the van and it lurched badly in forward, jerking like the torque converter was not functioning, and causing the van to die. I restarted a couple of times and got the van to go forward, still lurching.

Finally got it to drive a bit at low accelleration, it shifted through the gears OK, but shifted to 4th at about 30 mph (800 rpm's) and did not want to downshift normally.

Took the van home jerking badly from a "california-roll" stop, and checked all the wires where I may have knocked something loose.
Tried to drive again, same lurching, even in reverse now (before reverse seemed OK), and barely able to get van to get going.

Any ideas would be appreciated!

Dean.