Flexplate is broken or Crank bolts holding flexplate to crank are sheared off.
Automatics use a Flexplate, Manual transmissions use a Flywheel
Transmission needs to come out.
And maybe the engine, depending on condition of crank.
When you lost power to wheels was when the connection between Crank shaft and Flexplate was severed.
The Flexplate is the part you see that has the Ring Gear attached, starter motor turns the ring gear on the edge of the flexplate, flexplate is bolted to the crank shaft so it will turn the crank shaft/engine when ring gear turns.
Transmission/Torque converter is bolted to the Flexplate, Flexplate is connected to crank shaft, so when engine is running transmission is also running, doesn't mean it is in gear but is running, pumping ATF.
So no power in gear and no turning of engine by starter motor means flexplate is no longer connected to the engine/crankshaft
Look at post #11 here: http://www.explorerforum.com/forums/...d.php?t=135318
And post #7 here: http://www.ford-trucks.com/forums/13...nnot-find.html
Shows the center has been ripped out of a flexplate