Trans problem, need advice

Update: I dumped the fluid and changed the filter. I tightened the low reverse band and backed off 1/4"+. Filled it with Ford type F fluid.
I got the chance to roadtest it and problems seem to be solved. I'll know for sure tomorrow.
The old fluid was clean but there was some band material in the pan, not to much. But for now, its backing up with purpose and leaving with authority!
Thanks for the replies and advice to this thread!