[beamn7]

There are multiple wiring setups for the 700R4. When I built mine, I configured the pressure switches on the valve body so that when the ecm would apply ground for lockup, it went through an external relay I installed that would close when the 4th gear pressure switched opened up which tells the ecm to reduce egr flow therefore only allowing lockup in 4th. Stock it would apply in 2nd....
How many wires do you have going into the transmission at the 4 pin connector (usually 3 or less wires) and what are their colors? On mine one is + that is interupted by stepping on the brake, one is a ground that is applied by the ECM once predetermined values are met and a lock up signal is given and the other is a signal wire back to the ECM. Like I said though, there are multiple configurations depending on ESC or no ESC, C or K, trans code (stamped on pass side of trans at back just above pan), etc.... My 85 has no vac switch....