My BF's 95' B2500 Ram Van won't shift into O/D. Light on switch stays on. Tried replacing switch but didn't fix the issue. Replaced the Transmission less than 6 months ago. If it's the O/D Solenoid how hard is that to replace and where is it located.

Need to figure out why the light is staying on. The switch just sends a momentary voltage signal to the PCM, the PCM then turns on the light, and locks out O/D. The switch state should reset every time the van is shut off.... If it's not, then the PCM is disabling O/D for some other reason.... If you still have warranty on your trans, have a chat with the folks that installed it.