Fuel gauge “bouncing”

It’s got to be. Can the tank itself cause a bad ground? Attached are pics of the current ground connection.

Some further information. I did some more testing today. I tested a brand-new Sending unit connected to the same wires and grounding location is the current in-tank unit, and it worked just fine. Gauge was reading perfectly. However, when I hooked up some brand-new wires to the current in-tank unit, we went back to 3 o’clock or empty. We had pulled the current in-tank unit out and tested it a couple weeks ago, and it was working fine. Something about being in the tank is causing issues.

No sir, nothing. I think I’m looking at another tank drop and new sending unit. Yippee for me :)

Well, I'm here to publicly admit my stupidity and eat some humble pie. A big slice. Short story: the gauge is now working perfectly. Long story: we dropped the tank again and did some more testing with it off of the truck. During that testing, my wife noticed that the float of the sending unit was barely touching the fuel when it was set down in the tank. Basically, it was reading E because it was E! I was thinking it was a 16-gallon tank, so when I had five gallons in there, I thought I should have at least a quarter tank on the gauge. Turns out it is a 20-gallon tank, and the 4-5 gallons in there is the 'reserve' amount of fuel when it gets to E. I bought 5 more gallons of gas, dumped it, and we had almost a half tank on the gauge. Re-mounted the tank and it's reading the same. So, all in all, the gauge and wiring were all correct and working great, I just didn't have enough gas in the tank for the gauge to read it. Ugh. >Face palm

I do have a final question, related to my original question post: when I shake the truck, the gauge does bounce a bit. Is that fixable, or just the nature of the beast?

I will :) haha Thanks for all of your help!