[jsinton]

Not being able to hook up the lockup solenoid wouldn't cause it to do nothing. Also later Caravans had a electronic speedometer, replacing the mechanical ones. I would say you're just buying bad transmissions, as this is the primary reason these vans get junked. Are you sure you are able to connect all available connectors? Later transmissions were also computer controlled, although I'm not sure this makes a difference to you.