They aren't designed that way. It can occur when a new gas tank shape is developed, but an existing fuel level sending unit can be used from a previous design. It's common for a gas tank to have a smaller area near the bottom so the last remaining gas gets concentrated around the fuel pick-up screen. Being of a smaller area, it's natural for the float on the sending unit to drop faster. If it becomes necessary to design a new sending unit for a new car model, the resistor element in that sensor will be "non-linear", meaning it will change values at different rates at different positions. That will take into account the non-linear shape of that gas tank.
I've had vehicles with the same fuel gauge performance. For the first 200 miles, the gauge stayed at 'full", then it dropped quickly over the next 200 miles. What's more noteworthy is most gauges are designed to read "empty" when there's still a few gallons in the tank. That's because some people tend to run the tank to empty before adding gas. Fuel pumps are run with electric motors, and those are cooled by the gas around them. Running the tank too low will allow the pumps to run too hot. That reduces their life expectancy.
Thursday, January 29th, 2026 AT 3:20 PM
