HEY GUYS I dont spend much time over here on the 12valve side, I have a Buddy that just bought a 96 12 valve 2500 2WD W/Auto trans and his O/D is not working. The O/D Off Light in the dash is working indicating the switch is doing its job..shifts great 1-3 but no O.D. Anyone now what would cause this :shrug:Richie

ANYONE:shrug:

Check the relays and fuses, try swapping the tranny relay with another.

  Wild and Free said:

Check the relays and fuses, try swapping the tranny relay with another.

Try to take out the T.P.Sensor,and clean it.I did It on my Cunnings,and the Overdrive works perfekt.

Also check the brakelight switch. Also scan the computer for any trans. codes.