Back in the 70's we had a John Deere 3020. As long as the fuel gage was wiggling the fuel level was fine. When it stopped it was time to head to the house for fuel. Went to work for a neighbor that had a John Deere 5020 and a 1466 International Harvester. The fuel gage in the 5020 behaved just like our 3020.
One day I was prepping a field for planting. Knew the fuel was low but I figured that as long as the file gage wiggled I was ok. Boy was I wrong. Had to walk 3 miles back to the house. After filling the tank and replacing the collapsed fuel filters, it took almost two hours to hand prime the fuel system and then bleed all the air out of the injectors. From then on I NEVER let the fuel level get any where close to empty.