My trans has always tried to creep in neutral and it works fine. Check your band adjustments front , the easy one and then try the rear " the one inside.
Creeping in Neutral due to a tight rear clutch pack isn't all that unusual but the OP also has a bind-up in Reverse which isn't normal.
This is why I brought up mismatched Converter and front pump. I've had it happen and this is exactly what it did to me. Not sure why it does it. But it did.
This pump and this conv were working fine for over
400 miles till the OD drum burn up due to no torrington
in the one thats in the shop now
