Fuel Gauge not reading correctly

99 2dr 4x4 Blazer

Just this past week my fuel gauge started showing as full then the next day it would show as empty (with the light on) then it would go back to full.

I've researched a couple of posts and they seem to be contradicting.

One would say replace the whole pump and another would say that there is a ground wire that isn't grounding properly.
Could someone clarify if there is a ground wire that my be faulty on the body and its location or do I have to deal with it until I either want to change the pump or the pump goes bad?

Thanks for all of the assistance.

99 2dr 4x4 Blazer

Just this past week my fuel gauge started showing as full then the next day it would show as empty (with the light on) then it would go back to full.

I've researched a couple of posts and they seem to be contradicting.

One would say replace the whole pump and another would say that there is a ground wire that isn't grounding properly.
Could someone clarify if there is a ground wire that my be faulty on the body and its location or do I have to deal with it until I either want to change the pump or the pump goes bad?

Thanks for all of the assistance.

Fuel sending units the 99 grounds at the ground splice pack on left side of dash.
You can check for good ground at the wiring plug in going to fuel pump module in tank.
If two black ground wires there check both for a good ground.

MT-2500 is mot likely right but overall how is your truck running?

Truck is running pretty good. I have a couple vacuum issues. The AC hisses a little and sometimes when I stop the I can hear the 4x4 egaging a little bit but other than that nothing is wrong.