99 Durango no reverse

I have a 99 dodge Durango 5.2 V8 and my reverse went out :(…when I put it in reverse I hear and feel it go into reverse and it sounds like something is spinning…I give it a little gas and the sound gets louder. I dropped the pan yesterday to see if any parts were in there and there was nothing and also adjusted the band…what do I do now?? Help me please!!