How far can your car drive when the "empty" light comes on? Your Mechanic has about 50 vehicles listed, where they've figured it out for you. Check the chart with the Make / Model / Fuel Remaining When Low Fuel Warning Light is Triggered / Miles Remaining When Low Fuel Warning Light is Illuminated.
My Wrangler will apparently drive another 47-58 miles, but I HATE TAKING THAT CHANCE. I usually fill up slightly before my gas light comes on.