
2. Remove and discard the old fuel
filter element.
3. Carefully clean the mating
surfaces.
Installation-both
The engine will not run properly if the fuel filter is not installed
in housing.
1. Install new fuel filter into the fuel filter housing.
2. Tighten cap onto fuel filter housing slowly, allowing fuel to soak into
the fuel filter element. Tighten cap until it contacts the housing.
After replacing the fuel filter, the engine will purge the trapped
air as it runs. The engine may run roughly and smoke until the air
is completely eliminated.
Using a fuel which has more than average impurities may require
the fuel filter to be replaced more frequently than the service
interval specifies.
Fuel filter replacement - Cummins B engine
Refer to your engine operator’s manual for service intervals and
procedures.
FUEL CONSUMPTION IMPROVEMENT MEASURES
There are two important factors you can control to improve fuel
economy: the mechanical condition of your vehicle and how you drive it.
A properly maintained vehicle will deliver better performance than a
neglected vehicle. Always follow your maintenance schedule to keep your
vehicle in top operating condition.
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Also, your driving habits have a significant influence on use of fuel. By
following these suggestions, you can stretch your fuel use:
•Avoid changes in speed as much as possible.
•Anticipate changing traffic conditions. Sudden stops and fast
acceleration waste fuel.
•Avoid extensive idling.
•Do not drive with your foot resting on the brake pedal.
Essentials of good fuel economy
Measuring techniques
Your best source of information about actual fuel economy is you, the
driver. You must gather information as accurately and consistently as
possible. Fuel expense, frequency of fill-ups or fuel gauge readings are
NOT accurate as a measure of fuel economy. We do not recommend
taking fuel economy measurements during the first 1,000 miles
(1,600 km) of driving (engine break-in period). You will get a more
accurate measurement after 2,000–3,000 miles (3,000 km–5,000 km).
The advertised fuel capacity of the fuel tank(s) on your vehicle is equal
to the rated refill capacity of the fuel tank(s) as listed inFuel tanksin
this chapter. The advertised capacity is the amount of 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 small amount of usable fuel
remaining in the fuel tank after the fuel gauge indicates empty.
The amount of 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.
Filling the tank
For consistent results:
•Use the same fill rate setting (low - medium - high) each time during
filling.
•Allow three automatic click-offs when filling.
•Always use fuel of a known quality, preferably a national brand.
•Have the vehicle loading and distribution the same every time.
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•When refueling a vehicle equipped with dual fuel tanks, if the two
tanks are not filled equally, the fuel gauge reading may fluctuate
slightly until the fuel level between the two tanks balance out and
become equal.
Your results will be most accurate if your filling method is consistent.
Note:For vehicles equipped with dual fuel tanks, engine performance
may degrade if fuel is not added to both tanks when refueling.
Calculating fuel economy
1. Fill the fuel tank(s) completely and record the initial odometer
reading (in miles or kilometers).
2. Each time you fill the tank(s), record the amount of fuel added (in
liters or gallons).
3. After at least three to five tank fill-ups, fill the fuel tank(s) 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:
•Divide total miles traveled by total gallons used.
•Multiply liters used by 100, then divide by total kilometers traveled.
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
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.
•Anticipate stopping; slowing down may eliminate the need to stop.
•Sudden or hard accelerations may reduce fuel economy.
•Slow down gradually.
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![FORD F650 2005 11.G Owners Manual •Driving at reasonable speeds (traveling at 55 mph [88 km/h] uses 15%
less fuel than traveling at 65 mph [105 km/h]).
•Using the air conditioner or defroster may reduce fuel economy.
•Resting yo FORD F650 2005 11.G Owners Manual •Driving at reasonable speeds (traveling at 55 mph [88 km/h] uses 15%
less fuel than traveling at 65 mph [105 km/h]).
•Using the air conditioner or defroster may reduce fuel economy.
•Resting yo](/manual-img/11/5071/w960_5071-198.png)
•Driving at reasonable speeds (traveling at 55 mph [88 km/h] uses 15%
less fuel than traveling at 65 mph [105 km/h]).
•Using the air conditioner or defroster may reduce fuel economy.
•Resting your foot on the brake pedal while driving may reduce fuel
economy.
Conditions
•Carrying unnecessary weight may reduce fuel economy.
•Fuel economy may decrease with lower temperatures during the first
8–10 miles (12–16 km) of driving.
•Flat terrain driving improves fuel economy over hilly roads.
•Transmissions give their best fuel economy when operated in the top
cruise gear and with steady pressure on the accelerator.
•Close windows for highway driving.
NOISE EMISSIONS–EXTERIOR
In order to comply with the federal exterior noise regulations, your
vehicle may be equipped with noise emission items. Depending on the
vehicle configuration, it may have all or some of the following items:
Air Intake System
•Air Cleaner:should be inspected and its location should not be
altered. Do not alter inlet and outlet piping.
Body
•Wheel Well:splash shields, cab shields and under-hood insulation
should be inspected for deterioration, dislocation, and orientation.
Cooling System
•Check the fan for damage to blades; replace, if damaged, with the
recommended parts. Inspect for fan to shroud interference, and any
damage to shroud such as cracks and holes.
•The fan ratio should not be changed and the fan spacer dimensions
and positions should not be altered.
•Inspect the fan clutch for proper operation, make sure that the fan is
disengaged when cooling of the engine is not required.
•Check for proper operation of radiator shutters, if equipped. The
shutters should be open during normal operating temperatures.
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Engine and Driveline System
•Transmission Enclosure:inspect for cracks, holes, and tears. Clean
any deposits such as oil, dirt, and stones.
•Engine valve covers and block covers are made to damp out engine
mechanical noise and, if needed, should be replaced with
recommended parts. Check for mechanical isolations.
Exhaust System
•Inspect the exhaust system for leaks at various joint connections and
tighten the clamps.
•Do a visual inspection for cracks or holes in the muffler and tail pipe.
•Always use the recommended parts when items need to be replaced.
•The tail pipe elbow or offset tail pipe orientation must not be changed
from the standard position as originally received.
•To avoid abnormal changes in vehicle sound levels, it is necessary for
the owner to perform inspections and necessary maintenance at the
intervals shown in theGeneral Maintenance Informationsection.
CHASSIS-MOUNTED CHARGE AIR COOLER
Inspect charge air cooler daily
With the engine off, visually inspect the charge air cooler core assembly
for debris and clogging of external fins. Prior to engine operation,
remove any debris blocking the core.
•Turbocharger-to-charge air cooler
•Charge air cooler-to-intake manifold pipe
•Mounting bracket
•Chassis-mounted charge air cooler core
Inspect air intake piping
•Check for accumulation of salt deposits (where applicable). If present,
disassemble and clean the complete air intake piping system. If the
intake piping is pitted, use RTV silicone to seal joints against leakage.
•Check for loose hoses and clamps.
•Check for ruptured or collapsed hoses.
•Check air cleaner housing for cracks.
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ELECTRICAL SYSTEM INSPECTIONS
Periodically inspect electrical connectors on the outside of the cab, on the
engine and frame for corrosion and tightness. Exposed terminals such as
the fuel sender, cranking motor, alternator and feed-through studs should
be cleaned and re-coated with a lubricant sealing grease such as Motorcraft
XG-3, or equivalent. This should include the ground cable connector for
batteries, engine and cab as well as the jump starting stud.
Accessory feed connections
Vehicle electrical systems are complex and often include electronic
components such as engine and transmission controls, instrument panels,
ABS, etc. While most systems operate on battery voltage (12 volts),
some systems can be as high as 90 volts or as low as five volts. Refer to
the Electrical Circuit Diagram Manuals, available from your vehicle’s
manufacturer, to assure that any additional body lights and accessories
are connected to circuits that are both appropriate and not overloaded.
No modification should be made to any vehicle control system without
first contacting your dealer.
SUSPENSION INSPECTION
Note:Do not adjust air suspension height to any setting other than the
specified setting. Altering the height setting will change the driveline
angle and may result in unwarrantable component damage, such as
transmission component damage.
Verify drive axle air suspension height and height control valve
performance at engine lube oil change intervals.
Periodically:
•Check condition of spring leaves for evidence of fatigue, bending or
breakage.
•Check condition of suspension mounting brackets and bushings.
•Check that torque rod mounting fasteners are tight.
•Check to be sure the suspension alignment is maintained at all time.
•Check U-bolts after the chassis has been operating under load for
1,000 miles (1,600 km) or six months, whichever comes first, the
U-Bolt nuts must be re-torqued. The U-Bolt nuts thereafter must be
re-torqued every 36,000 miles (58,000 km). The U-Bolt and nut
threads and seats should be cleaned and lubricated to assure a“like
new”condition when re-torquing.
Note:See theU-Bolt Nut Torquechart later in this section.
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REAR AXLE LUBRICANT
Refer to your general maintenance information section for rear axle
lubricant level checks and lubricant change intervals.
Your rear axle may be filled with an optional synthetic lubricant which
allows the use of extended service intervals. A tag on the filler plug will
identify the use of the synthetic lubricant.
Use only a lubricant that meets manufacturer specifications (refer to
Lubricant specificationsin this chapter).
Use of a non-approved rear axle lubricant may cause internal axle
component damage.
Check your rear axle lubricant level using the following procedure:
1. Park the vehicle on level ground.
2. Set the parking brake and shift into N (Neutral) (automatic
transmission) or 1 (First) (manual transmission) and turn the engine off.
3. Clean any dirt from around the rear axle filler plug.
4. Remove the filler plug and inspect the lubricant level.
5. The lubricant level should be up to the bottom of the filler plug
opening.
6. If necessary, add enough lubricant through the filler plug opening so
that the lubricant level is at the bottom of the opening.
7. Clean and install the filler plug securely.
Drain and refill your rear axle lubricant using the following procedure:
1. Drain the rear axle while the lubricant is warm.
2. Park the vehicle on level ground.
3. Set the parking brake and shift into N (Neutral) (automatic
transmission) or 1 (First) (manual transmission) and turn the engine off.
4. Clean any dirt from around the rear axle filler and drain plugs.
5. Remove the filler and drain plugs and drain the lubricant into a
suitable container. Dispose all used automotive fluids in a responsible
manner following your local authorized standards.
6. Clean and install the drain plug securely.
7. Add enough lubricant through the filler plug opening so that the
lubricant level is up to the bottom of the opening.
8. Clean and install the filler plug securely.
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In some types of operation, and where operating conditions are
extremely severe (such as in deep water, mud or unusually dusty
conditions), the vehicle may require lubrication after every 24 hours of
operation.
Maintenance intervals
Maintenance intervals are provided for three types of general vehicle
environments: On-Highway, City and Severe Service. In all applications,
the actual interval is determined by monitoring kilometers (miles) and
time and when the engine is due for an oil change. When the engine oil
change is required prior to the truck lubrication interval, it is
recommended that the lubrication be performed at the same time in
order to reduce your vehicle’s time out of service.
•On-Highway:60,000 miles (96,000 km) or more annually.
•City:59,000 miles (95,000 km) or less annually.
•Severe Service:20,000 miles (32,000 km) or less annually on/off
road in dirty conditions.
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