Let me give you a bit of information.
The AOD transmission does not have a lock up torque convertor.
It is a conventional convertor with a damper connected to the cover and splined to the direct clutch drum.
Once the transmission shifts into 3rd gear the convertor is taken out of the equation.
It works as if there were a pipe welded between the crank pulley and drive shaft yoke.
Then the "OD" overdrive kicks in, which lowers engine RPM's.
There is no lockup valve.
http://www.troublecodes.net/members/stu/AOD_GD.pdf
What you may be experiencing is convertor stall, common for any convertor, lock up or not.
Different engines will produce a different stall rate on the same convertor.
Put that convertor behind a 3.0 and you will get X stall speed.
Stuff it behind a 351 Cleavland and you will get XXXX stall speed.
You must get the no shift condition corrected first.
