I bought a 95 (47rh) truck that doesn't have OD or lockup. The OD off button sometimes lights up when pressed. OD and lockup up tried to engage one time. There's and old OD off switch layin on the floor. Other than checking 12 volts to center pin of trans connector, what are the fuses/ relays in the load center associated with OD and lockup?

 

I don't think the fuses and relays are for the o/d and lock up?

 

I would start with doing a service on the transmission and looking in the pan ... metal means problems ... grey matter means worn clutches ..... go from there ........ if that dosent solve anything ... check speed sensor and tps for correct voltage....