One day I went to drive in reverse to back up and it didn't and I heard a noise underneath. I can't describe the noise.

It won't drive in reverse, but it will go forwards and shifts through all the gears.

There was no slipping gears or any warnings of anything going bad.

The fluid level was at the Safe/Fill line , but not below it.

I added more to see if it would work, but didn't.

What could it be?

What part in the transmission should be replaced that could cause no reverse?

When driving after reverse went out, at low rpms about 1,000-2,000rpms 30mph it would make like a humming noise and the noise would then be heard at 3,000+rpms past 50mph,

but, the noise stopped after a while

and still no reverse...


but shifts good through all gears going forwards


2001 Dodge Ram 1500, V6 42RE transmission

 

I think there is a piece that holds the rear band in place. I don't know if you could reinstall it and adjust the band or not. My guess is you need yours rebuilt. I bought a reman and swapped them when mine failed.

 

Most likely the rear band has failed or the pivot pin or lever has dislodged as 2bit suggested.