Hello, folks. I'm new to the board, and to PSD ownership. I just purchased a 1996 F250 4x4 with 7.3L PSD and EO4D transmission, 145k miles. Already, this forum has helped me out (so I joined). The transmission shifts normally, but the Overdrive "Off" lamp doesn't light up. After reading here a bit, it's a good bet the wires from the shifter-end OD button are broken in the column. Helpful to know - and to know I need to get it fixed as the lamp is the 'idiot' light for the tranny. Good info.