Gas gauge is possessed!!

My gas gauge swings from full to half and back to full, then to empty and back to half while driving down the road... my guess is the sending unit in the tank needs to be replaced... any other ideas before I drop the tank?

mine does work at all, stays at full except when i shut it off then it goes back down.

Look this thread.
Fuel Gauge, Air Bag Light, Rear Hatch Release

its your sending unit
i was checking my fuel pump one day and checked the wrong wires and fried the sending unit and gauge is being retarded i would bet a million dollars its the sendind unit
your welcome for fixing the problem

mine does same thing , its not the sending unit, garage tried 2 new one , thinking 1st they got was bad, its not that, anyother ideas?