2003 FORD F SERIES MOTORHOME AND COMMERCIAL CHASSIS engine

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 quality gasoline, preferably a national brand.
•Use the same side of the same pump and have the vehicle facing the
same direction each time you fill up.
•Have the vehicle loading and distribution the same every time.
Your results will be most accurate if your filling method is consistent.
Calculating fuel economy
1. Fill the fuel tank completely and record the initial odometer reading
(in kilometers or miles).
2. Each time you fill the tank, record the amount of fuel added (in liters
or gallons).
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. Follow one of the simple calculations in order to determine fuel
economy:
Calculation 1:Multiply liters used by 100, then divide by total
kilometers traveled.
Calculation 2:Divide total miles traveled by total gallons used.
Keep a record for at least one month and record the type of driving (city
or highway). This will provide an accurate estimate of the vehicle’s fuel
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economy under current driving conditions. Additionally, keeping records
during summer and winter will show how temperature impacts fuel
economy. In general, lower temperatures give lower fuel economy.
Driving style — good driving and fuel economy habits
Give consideration to the lists that follow and you may be able to change
a number of variables and improve your fuel economy.
Habits
•Smooth, moderate operation can yield up to 10% savings in fuel.
•Steady speeds without stopping will usually give the best fuel
economy.
•Idling for long periods of time (greater than one minute) may waste
fuel.
•Anticipate stopping; slowing down may eliminate the need to stop.
•Sudden or hard accelerations may reduce fuel economy.
•Slow down gradually.
•Driving at reasonable speeds (traveling at 88 km/h [55 mph] uses 15%
less fuel than traveling at 105 km/h [65 mph]).
•Revving the engine before turning it off may reduce fuel economy.
•Using the air conditioner or defroster may reduce fuel economy.
•You may want to turn off the speed control in hilly terrain if
unnecessary shifting between third and fourth gear occurs.
Unnecessary shifting of this type could result in reduced fuel
economy.
•Warming up a vehicle on cold mornings is not required and may
reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
•Combine errands and minimize stop-and-go driving.
Maintenance
•Keep tires properly inflated and use only recommended size.
•Operating a vehicle with the wheels out of alignment will reduce fuel
economy.
•Use recommended engine oil. Refer toLubricant specificationsin
this chapter.
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•Do not turn off the ignition while your vehicle is moving, especially at
high speeds.
•Have the items listed in your scheduled maintenance guide performed
according to the specified schedule.
The scheduled maintenance items listed in the scheduled maintenance
guide are essential to the life and performance of your vehicle and to its
emissions system.
If other than Ford, Motorcraft or Ford-authorized parts are used for
maintenance replacements or for service of components affecting
emission control, such non-Ford parts should be equivalent to genuine
Ford Motor Company parts in performance and durability.
Do not park, idle, or drive your vehicle in dry grass or other dry
ground cover. The emission system heats up the engine
compartment and exhaust system, which can start a fire.
Illumination of the “Service Engine Soon” light, charging system warning
light or the temperature warning light, fluid leaks, strange odors, smoke
or loss of engine power, could indicate that the emission control system
is not working properly.
Exhaust leaks may result in entry of harmful and potentially
lethal fumes into the passenger compartment.
Do not make any unauthorized changes to your vehicle or engine. By
law, vehicle owners and anyone who manufactures, repairs, services,
sells, leases, trades vehicles, or supervises a fleet of vehicles are not
permitted to intentionally remove an emission control device or prevent
it from working. Information about your vehicle’s emission system is on
the Vehicle Emission Control Information Decal located on or near the
engine. This decal identifies engine displacement and gives some tune up
specifications.
Please consult yourWarranty Guidefor complete emission warranty
information.
Readiness for Inspection/Maintenance (I/M) testing
In some localities, it may be a legal requirement to pass an I/M test of
the on-board diagnostics system. If your “Check Engine/Service Engine
Soon” light is on, refer to the description in theWarning lights and
chimessection of theInstrument clusterchapter. Your vehicle may not
pass the I/M test with the “Check Engine/Service Engine Soon” light on.
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If the vehicle’s powertrain system or its battery has just been serviced,
the on-board diagnostics system is reset to a “not ready for I/M test”
condition. To ready the on-board diagnostics system for I/M testing, a
minimum of 30 minutes of city and highway driving is necessary as
described below:
•First, at least 10 minutes of driving on an expressway or highway.
•Next, at least 20 minutes driving in stop-and-go, city-type traffic with
at least four idle periods.
Allow the vehicle to sit for at least eight hours without starting the
engine. Then, start the engine and complete the above driving cycle. The
engine must warm up to its normal operating temperature. Once started,
do not turn off the engine until the above driving cycle is complete.
CHECKING AND ADDING POWER STEERING FLUID
Check the power steering fluid.
Refer to the scheduled maintenance
guide for the service interval
schedules. If adding fluid is
necessary, use only MERCONAT F.
1. Start the engine and let it run until it reaches normal operating
temperature (the engine coolant temperature gauge indicator will be
near the center of the normal area between H and C).
2. While the engine idles, turn the steering wheel left and right several
times.
3. Turn the engine off.
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78

TRANSMISSION FLUID
Checking automatic transmission fluid (if equipped)
Refer to your scheduled maintenance guide for scheduled intervals for
fluid checks and changes. Your transmission does not consume fluid.
However, the fluid level should be checked if the transmission is not
working properly, i.e., if the transmission slips or shifts slowly or if you
notice some sign of fluid leakage.
Automatic transmission fluid expands when warmed. To obtain an
accurate fluid check, drive the vehicle until it is at normal operating
temperature (approximately 30 km [20 miles]). If your vehicle has been
operated for an extended period at high speeds, in city traffic during hot
weather or pulling a trailer, the vehicle should be turned off for about 30
minutes to allow fluid to cool before checking.
1. Drive the vehicle 30 km (20 miles) or until it reaches normal operating
temperature.
2. Park the vehicle on a level surface and engage the parking brake.
3. With the parking brake engaged and your foot on the brake pedal,
start the engine and move the gearshift lever through all of the gear
ranges. Allow sufficient time for each gear to engage.
4. Latch the gearshift lever in P (Park) and leave the engine running.
5. Remove the dipstick, wiping it clean with a clean, dry lint free rag. If
necessary, refer toIdentifying components in the engine compartment
in this chapter for the location of the dipstick.
6. Install the dipstick making sure it is fully seated in the filler tube.
7. Remove the dipstick and inspect the fluid level. The fluid should be in
the designated area for normal operating temperature or ambient
temperature.
Low fluid level
Do not drive the vehicle if the fluid
level is at the bottom of the dipstick
and the ambient temperature is
above 10°C (50°F).
Correct fluid level
The transmission fluid should be checked at normal operating
temperature 66°C-77°C (150°F-170°F) on a level surface. The normal
operating temperature can be reached after approximately 30 km
(20 miles) of driving.
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AIR FILTER MAINTENANCE
Refer to the scheduled maintenance guide for the appropriate intervals
for changing the air filter element.
When changing the air filter element, use only the Motorcraft air filter
element listed. Refer toMotorcraft Part Numbers.
Note:Do not start your engine with the air cleaner removed and do not
remove it while the engine is running.
Changing the air filter element
1. Loosen the clamp that secures
the air filter element in place.
2. Carefully separate the two halves
of the air filter housing.
3. Remove the air filter element
from the open end of the air filter
housing.
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4. Install a new air filter element, ensuring the arrow on the top half of
the air filter housing lines up with the notch on the bottom half of air
filter housing. Be careful not to crimp the filter element edges between
the air filter housing. This could cause filter damage and allow
unmetered air to enter the engine if not properly seated.
5. Replace the two halves of the air filter housing and secure the clamp.
INFORMATION ABOUT UNIFORM TIRE QUALITY GRADING
New vehicles are fitted with tires
that have a rating on them called
Tire Quality Grades. The Quality
grades can be found where
applicable on the tire sidewall
between tread shoulder and
maximum section width. For
example:
•Treadwear 200 Traction AA Temperature A
These Tire Quality Grades are determined by standards that the United
States Department of Transportation has set.
Tire Quality Grades apply to new pneumatic tires for use on passenger
cars. They do not apply to deep tread, winter-type snow tires,
space-saver or temporary use spare tires, tires with nominal rim
diameters of 10 to 12 inches or limited production tires as defined in
Title 49 Code of Federal Regulations Part 575.104(c)(2).
U.S. Department of Transportation-Tire quality grades:The U.S.
Department of Transportation requires Ford to give you the following
information about tire grades exactly as the government has written it.
Treadwear
The treadwear grade is a comparative rating based on the wear rate of
the tire when tested under controlled conditions on a specified
government test course. For example, a tire graded 150 would wear one
and one-half (1 1/2) times as well on the government course as a tire
graded 100. The relative performance of tires depends upon the actual
conditions of their use, however, and may depart significantly from the
norm due to variations in driving habits, service practices, and
differences in road characteristics and climate.
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Follow these guidelines when using snow tires and chains:
•Use only SAE Class S chains.
•Install chains securely, verifying that the chains do not touch any
wiring, brake lines or fuel lines.
•Drive cautiously. If you hear the chains rub or bang against your
vehicle, stop and re-tighten the chains. If this does not work, remove
the chains to prevent damage to your vehicle.
•If possible, avoid fully loading your vehicle.
•Remove the tire chains when they are no longer needed. Do not use
tire chains on dry roads.
•The suspension insulation and bumpers will help prevent vehicle
damage. Do not remove these components from your vehicle when
using snow tires and chains.
MOTORCRAFT PART NUMBERS
Component 6.8L V10 engine
Air filter element FA-1634
Battery BXT-65-750
Fuel filter FG-986B
Oil filter FL-820-S
PCV valve EV-233
Spark plugs* AWSF-22E
*Refer to Vehicle Emissions Control Information (VECI) decal for spark
plug gap information.
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