Originally Posted by rhite95
How much fuel is in the tank when the light comes on I have a 05 FX4?
They vary a bit truck to truck but it's easy to determine how much is left.
Just fill it up when the light first comes on. Subtract the gallons pumped from 19.5 (the nominal tank capacity of a Supercab like yours). The difference is the approximate number of gallons that were remaining when the light came on.
Mine takes about 16 gallons to refill, so my light comes on with about 3.5 gallons left.