2001 dodge 1500 4x4 no reverse

Same problem with 2002 1500, was told I would need a rebuild. Will update if I find any helpful info.

Question to you before i can answer, do you have an abs warning light on? If so you need to replace the bad abs sensors. I just went through this with another chrysler product. Ive been a mechanic for years and would have never thought everything in the drive line runs through the sensors. One can go out and its not a big deal you just lose your cruise control and traction control, same thing if two go out, in my case i had three of them out and the vehicle wouldnt shift correctly or stay in reverse unless i left my foot on the brake at all times. I replaced the sensors and it fixed everything.