At this juncture we really don't know how its suppose to work by design. I'm going to try to research this.
However, I've had the low fuel message come on three different times, at which the tank took 28, 29, and 26 gallons respectively. These fills appear to have a correlation to the actual gas mileage on the tank prior to filling. This makes me suspect that at the very least the computer is throwing up the low fuel message based on the average gas mileage of the current tank. The lower the average gas mileage, the sooner the computer will cause a low fuel message.
And one person has stated they got 32 gallons into the 33 gallon tank at fill-up.
Best regards,
Dusty
2019 Ram 1500 Laramie Quad Cab 2WD, 5.7 Hemi, 8HP75, 3.21 axle, factory dual exhaust, 18” wheels. Now at: 005138 miles.