Fuel gage jumping!!!

My 89' Sub fuel gage is jumping all over (High-off the gage and down to normal) when the tank is from 3/4-1/2 full. It does not read below 1/4 tank. Is this just the sending unit, or something else? Ideas?
Thanks!!!
- Ingoldx1

Same thing is happening to me! I haven't had it checked yet but will soon and let you know.

Yup, it's the sending unit.

Thanks!!!!!
Ingoldx1