FORD 2013 F-550 v.2 - Manual (Page 196)

FUEL CONSUMPTION
Filling the Tank
The advertised capacity is the indicated capacity and the empty reserve
combined. Indicated capacity is the difference in the amount of fuel in a
full tank and a tank when the fuel gauge indicates empty. Empty reserve
is the amount of fuel in the tank after the fuel gauge indicates empty.
Note: The amount of usable fuel in the empty reserve varies and should
not be relied upon to increase driving range. When refueling your vehicle
after the fuel gauge indicates empty, you might not be able to refuel the
full amount of the advertised capacity of the fuel tank due to the empty
reserve still present in the tank.
For consistent results when filling the fuel tank:
• Turn the ignition off before fueling; an inaccurate reading results if the
engine is left running.
• Use the same fill rate (low–medium–high) each time the tank is filled.
• Allow no more than two automatic click–offs when filling.
Results are most accurate when the filling method is consistent.
Calculating Fuel Economy
Do not measure fuel economy during the first 1000 miles
(1600 kilometers) of driving (this is your engine’s break-in period); a
more accurate measurement is obtained after 2000 miles–3000 miles
(3200 kilometers–4800 kilometers). Also, fuel expense, frequency of
fill-ups or fuel gauge readings are not accurate ways to measure fuel
economy.
1. Fill the fuel tank completely and record the initial odometer reading.
2. Each time you fill the tank, record the amount of fuel added.
3. After at least three to five tank fill-ups, fill the fuel tank and record
the current odometer reading.
4. Subtract your initial odometer reading from the current odometer
reading.
5. Calculate fuel economy as follows:
Standard: Divide miles traveled by gallons used.
Metric: Multiply liters used by 100, then divide by kilometers traveled.
Fuel and Refueling 195
2013 F-250/350/450/550 (f23)
Owners Guide gf, 2nd Printing, December 2012
USA (fus)