FORD 2003 F-550 v.1 - Manual (Page 210)

Replace the fuel filter with an authorized Motorcraft part. The
customer warranty may be void for any damage to the fuel system
if an authorized Motorcraft fuel filter is not used.
ESSENTIALS OF GOOD FUEL ECONOMY
Measuring techniques
Your best source of information about actual fuel economyis you, the
driver. You must gather information as accuratelyand consistentlyas
possible. Fuel expense, frequencyof fill-ups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economymeasurements during the first 1,600 km (1,000
miles) of driving (engine break-in period). You will get a more accurate
measurement after 3,000 km–5,000 km (2,000 miles-3,000 miles).
Filling the tank
The advertised fuel capacityof the fuel tank on your vehicle is equal to
the rated refill capacityof the fuel tank as listed in the Refill capacities
section of this chapter.
The advertised capacityis the amount of the indicated capacityand the
emptyreserve combined. Indicated capacityis the difference in the
amount of fuel in a full tank and a tank when the fuel gauge indicates
empty. Empty reserve is the small amount of fuel remaining in the fuel
tank after the fuel gauge indicates empty.
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 engine/ignition switch to the off position prior to refueling,
an error in the reading will result if the engine is left running.
• Use the same filling rate setting (low — medium — high) each time
the tank is filled.
• Allow no more than 2 automatic click-offs when filling.
• Always use fuel with the recommended octane rating.
• Use a known qualitygasoline, preferablya national brand.
• Use the same side of the same pump and have the vehicle facing the
same direction each time you fill up.
Maintenance and Specifications
210